Samuel James "Sam" Witwicky is a human who collaborates with the Autobots after he buys a down-runned car that turns out to be an Autobot known as Bumblebee. He is the main human protagonist of the Transformers film franchise.
|“||That kid is an alien bad news magnet.||”|
—Simmons commenting on Sam, Dark of the Moon
Official Movie Prequel comics
Years later, Sam discovers the concept of riding around in cars to cruise for chicks. He looks to his box of priceless historical artifacts, and his thoughts turn to eBay...
- Actor: Shia LaBeouf
After getting an undeserved A- for his genealogy report, Sam and his father went to buy a car. Though they passed a Porsche car lot, Ron was actually playing a cruel joke on his son (real smart, considering that he'll eventually get power of attorney someday). Going to Bobby Bolivia's car lot, they went shopping for a used car. Sam spotted a Camaro that he liked, but Ron, who is a cheapskate, refused to go over four thousand dollars. However, when all the windows in the car lot suddenly exploded, Bolivia agreed to four thousand.
Taking his friend Miles to the lake, they encountered Mikaela and her boyfriend Trent. Trent pretty much told them to get lost, but Mikaela then dumped Trent. Realizing he had his one shot, Sam abandoned Miles and offered to give Mikaela a ride home. When his car had some engine trouble, Mikaela looked under the hood and was quite impressed with the layout of the Camaro's engine, though Sam was more impressed with the layout of Mikaela. She was wearing a sleeveless midriff top, short denim skirt, and gleaming form perspiration. After giving her a ride home, Mikaela asked Sam if he thought she was shallow. Sam awkwardly replied that he thought there was "more than meets the eye...with you". After berating himself for his lame pickup line, Mikaela waved goodbye from her porch, and Sam felt that he made progress, and said he loved his car.
Later that night, his car suddenly left. Believing it was being stolen, Sam followed it to an abandoned junkyard. To his shock and horror, the car was alive. Sam left his last words to his parents and his dog Mojo, where he acknowledged that he owned Busty Beauties that were given to him by Uncle Charles, then investigated. Some police came and arrested him, and an overzealous cop, believing him to be a junkie, ripped him a new one. Returning home, Satan's Camaro arrived, and Sam fled ignominiously on his mother's pink bike. He hit the cement hard in front of Mikaela, and soon found a police car. He demanded the officer's help... at which point said police car turned into an even scarier car. After throwing Sam onto a nearby car, the police car demanded the location of Sam's eBay items, but Sam fled and ran into Mikaela. The Camaro arrived and took them to a power plant, where the two cars fought it out, while Sam was chased by a spastic abomination who pantsed him. Mikaela was able to cut it's head off, which Sam punted.
Sam and Mikaela approached the Camaro, who could only speak through his radio, and offered a ride. Mikaela was hesitant, but Sam convinced her to get in. While driving, Sam had shotgun, but Mikaela refused to sit in the driver's seat. Sam suggested that she sit in his lap. Safety first, right? She agreed, then admitted to Sam that it was a smooth move on his part. He liked the moment. As Mikaela asked why if the robot was so advanced, then why did he turn into a piece of crap Camaro? Insulted, the car forced them out. As Sam lamented how four thousand dollars had driven off, the car returned as a 2009 Camaro. Taking the teens to an observatory, they watched as four meteors entered Earth's atmosphere, during which Mikaela instinctively reached out for Sam's hand. They were then escorted to an abandoned alley, where they met the biggest surprises of them all. Four other cars transformed into robots. The lead robot, after inquiring about Sam's identity, introduced himself as Optimus Prime, leader of the Autobots, autonomous robotic lifeforms from a planet known as Cybertron. Prime introduced Jazz, his first lieutenant, Ironhide, his weapons expert, Ratchet, their medical officer (who claimed that Sam's pheromone level indicated that he wanted to mate with Mikaela, embarrassing both teens), and identified the Camaro as Bumblebee, Sam's appointed guardian. Optimus explained their mission to locate the All Spark, the betrayal of Megatron and the Decepticons, and how Archibald Witwicky's glasses played a vital role in finding the All Spark.
Going to his house, Sam and Mikaela frantically searched for the glasses, but the Autobots were somewhat impatient and totally wrecked his dad's backyard. Since Optimus Prime caused a lot of noise, Sam's parents thought it was an earthquake and went to check on Sam. After finding the door locked, Sam's father was seriously furious and when Sam finally opened the door, Sam's mother accused Sam of masturbating. After finding the glasses, government agents arrived. They wore Black suits and neckties, typical government Their leader, who was also dressed in black (with a clip-on tie), Agent Simmons took Sam and Mikaela into custody, separating Sam from his parents. Simmons went bad cop on Sam, threatening him with life imprisonment and revealing Mikaela's criminal record. Just as Simmons demanded answers about aliens, Prime intercepted the convoy, and the Autobots totally outclassed the agents. Sam demanded to know what Sector Seven was, but a backup team arrived. Prime took Sam and Mikaela to hide under a bridge, but they nearly fell to their deaths. Bumblebee saved them, but was captured, and Sam and Mikaela recaptured.
Taken to Hoover Dam, Simmons tried the awkward role of good cop, but Sam was uninterested in talking. Tom Banachek tried to bribe him, and Sam demanded the freeing of Bumblebee, his parents, and the expunging of Mikaela's criminal record. Taking them into the Dam, Sector Seven showed them N.B.E.-1, who Sam recognized as Megatron. He explained Megatron's goals, and the purpose of the All Spark. However, the spastic abomination that pantsed him sent a message to the Decepticons, who attacked. Sam implored Sector Seven to release Bumblebee, saying he could help, which Captain Lennox assisted by putting a gun to Simmons' chest. Bumblebee converted the All Spark to a smaller form, and the soldiers escorted the two teens and Bumblebee to Mission City, soon augmented by the Autobots.
Upon reaching Mission City, an F-22 Raptor was spotted, which Ironhide recognized as Starscream. Starscream attacked, damaging Bumblebee's legs, and a tank attacked the soldiers. As the Autobots and the soldiers went to deal with the tank, Mikaela arrived to with a tow truck to remove Bumblebee from the battle. Megatron soon arrived and killed Jazz, and Lennox ordered Sam to take the All Spark to a building to be escorted out of the city. Despite his refusal to leave, Bumblebee handed the Cube to Sam, urging him to go. Sam was pursued by Megatron, Starscream, and a helicopter, with Ratchet and Ironhide providing protection, but they were injured by Starscream, and Sam was forced to leave without them. During his flight, Sam dropped the All Spark, causing some nearby machines to come to life. Reaching the building, Sam ignited a flare, but his ride was destroyed by Starscream.
Cornered on the roof, Megatron demanded the All Spark, in exchange for living to be his pet, but Sam refused. Megatron used his flail to knock Sam off the roof, but Sam was saved by Optimus Prime. Telling Sam to hold onto the cube, Prime tried to scale down the building, but Megatron knocked them all off. Prime managed to shield Sam from any serious injury, however. Prime expressed admiration for Sam's efforts, and told him that if he couldn't defeat Megatron, Sam was to merge the Cube with his spark, destroying both Prime and the All Spark. However, Megatron was too powerful for Optimus to defeat alone, and Prime told Sam to push the cube into the Autobot's chest. Instead, Sam merged the All Spark with Megatron, killing him. Optimus extended his thanks, telling him he owed Sam a debt of gratitude. Bumblebee, who could now speak, requested permission to stay with Sam, to which Sam eagerly agreed. Sam and Mikaela entered into a relationship, and made out on Bumblebee's hood while Ironhide and Ratchet observed.
Sam really loves having a car.
In an alternate reality, Sam held the key to Earth's survival, and his attempt to destroy Megatron with the All Spark... failed. Sam was killed and Mikaela & Bumblebee mourn him still. Bumblebee wondered if there was another reality where Sam's attempt succeeded and the Decepticons didn't conquer the United States...
Revenge of the Fallen film
Sam prepares to go to college, but his parents have letting go issues. While he is looking through his mementos from Mission City, a shard of the All Spark falls out of his shirt into his hand and shocks him, causing him to see images of weird symbols in his head. He drops the shard and it burns through the floor, falling into the kitchen where it brings to life all of the appliances. Sam escapes and Bumblebee destroys the appliance bots. Afterward, he gives the shard to Mikaela, but is unable to admit he loves her saying he wants her to do it first which frustrates her. Sam ends up having to spill the bad news to Bumblebee - Bee can't come with him to college as freshmen aren't allowed to have cars and Sam tells Bumblebee to return to the other Autobots.
At college, Sam is freaked out by Leo Spitz, his roommate, and mortified by his mother who eats a pot brownie. He tries to get a change of rooms but fails. Sam misses his first web-cam date with Mikaela due to being dragged off to a party by his roommate, Leo and is hit upon by a co-ed named Alice. Before things can go too far, Bumblebee shows up to take him to Optimus Prime. Optimus asks for his help in convincing the United States government, but Sam refuses as he wants a normal life now by stating "This isn't my war" and doesn't think Optimus Prime truly needs him.
During his first day, he has a mental breakdown due to the information the All Spark put into his head and is kicked out of class. He realizes what the All Spark did to him and calls Mikaela to warn her about it. After beating Wheelie, she decides to come to him. Sam has another breakdown and starts drawing the symbols over everything after returning to his room. Alice and Leo show up and she kicks Leo out, forcing herself on Sam, who is unable to get away and doesn't see the tentacle she sends at him. He's saved by Mikaela's arrival, and Mikaela, sure she's caught him cheating on her, breaks up with him on the spot and leaves. Sam is attacked again by Alice and his screams for help draw Mikaela and Leo who's arrival distracts Alice and allows him to get away. Alice reveals herself to be a Decepticon Pretender and chases the three of them. They escape in a car hotwired by Mikaela and she kills Alice who continued to give chase to them.
Unfortunately, they are captured by Grindor who takes them to a resurrected Megatron, who is understandably unhappy with Sam killing him and plans to kill him, after he dissects his brain for the information he needs. Optimus and Bumblebee rescue them and Sam goes with Optimus while Mikaela and Leo go with Bumblebee. Sam witnesses Optimus battle Megatron, Starscream and Grindor all at once. Though killing Grindor, Optimus Prime is killed by Megatron right in front of Sam. Optimus Prime's last words are for Sam to run. Sam is saved by the other Autobots and goes on the run with Mikaela, Leo, Bumblebee, Skids and Mudflap while the other Autobots are taken into custody by the government.
Sam gets depressed over Optimus sacrificing himself to save him and decides to turn himself in after The Fallen's broadcast. The others convince him not to and turn to him as their leader. After realizing the symbols he keeps seeing are the key and after Skids and Mudflap are unable to translate them, he decides they will go see Leo's rival, "RoboWarrior" for help.
In Brooklyn, Leo finds RoboWarrior and when Sam and Mikaela are called in, they're shocked at who it is: former Agent Seymour Simmons of Sector Seven. Simmons initially refuses to help, but Sam convinces him to by showing him one of the symbols he keeps drawing. Simmons shows them drawings of symbols just like the ones Sam kept drawing and reveals that the Transformers have been on Earth a long time. He shows them pictures of suspected Cybertronians as well and Mikaela brings out her captured Decepticon Wheelie to identify the symbols. Wheelie is unable to translate them, but recognizes the pictures of the Cybertronians (Seekers) and is shocked they have pictures of them. Wheelie offers to lead them to the Seekers, the only ones who can translate the language.
Wheelie leads them to the Smithsonian and Sam revives the Seeker there with the All Spark shard. Too late Mikaela realizes that the Seeker is a Decepticon. The Seeker wakes up, but mostly disregards them at first. The Seeker reveals his name is Jetfire and he has defected to the Autobots. This causes Wheelie to defect as well. Sam draws the symbols in the ground with a knife and mentions The Fallen to Jetfire who remembers their mission and teleports them to Egypt via a Space bridge.
Sam injures his hand upon arrival and Mikaela bandages it. They demand an explanation from Jetfire and he explains where they are and the history of The Fallen and the Dynasty of Primes. Upon learning that only a Prime can defeat The Fallen and of the Matrix's power, Sam decides that they will find the Matrix and use it to bring Optimus back to life. Jetfire gives them the clue he has deciphered and passes off his mission to Sam before having them leave him behind.
Simmons figures out what part of the message means, and Sam has Simmons call Lennox to get Optimus' body to that location. Sam and his friends spend the night near the Great Pyramids of Giza. While talking with Mikaela, Sam realizes what the rest of the message means. The group travels to the mountains of Petra to find the Matrix, and thanks to the Twins antics, they find the tomb. Sam finds the Matrix, but it crumbles to sand in his hands. Desperate, he puts it in his sock and believes that it will still work. Sam and his group then head for the rendezvous point to meet up with Lennox and his soldiers so he can try to revive Optimus Prime.
They get close, but are attacked by Megatron and Starscream. Sam sends Bumblebee and the Twins off to distract them. Simmons and Leo go with the Autobots to help buy more time. Sam and Mikaela make it to an abandoned town nearby, but have to hide from the Decepticons. While hiding, an Insecticon finds them. Sam kills it, but it alerts the Decepticons to their presence.
Sam and Mikaela end up running, but are forced to stop when Skipjack shows up with his parents as hostages. Sam's parents try to get him to run, but Sam spots Bumblebee and distracts Skipjack long enough for him to sneak up. Bumblebee kills Skipjack and Ravage. Sam has him to take his parents, who finally accept that he has grown up, to safety. Sam and Mikaela run through the battle, as they run they takes off their jackets for unknown reaons and meet up with Lennox and Epps. They are nearly cornered by Mixmaster, but Jetfire returns to help and kills Mixmaster and Scorponok.
Unfortunately, after the Decepticons are bombarded by the Air Force, Sam rushes for Optimus too early, and is killed by a blast from Megatron. Lennox and a medic try to revive him, but fail. Even Mikaela admitting she loves him fails. In a vision-like state, Sam encounters the spirits of the Primes. The Primes tell him that he has displayed the qualities of a true leader and has earned the Matrix which has to be "earned" instead of "found", which is why it crumbled to dust when he picked it up. The Primes reveal that this has always been Sam's destiny, then resurrect him. As soon as he resurrects, Sam finally admits he loves Mikaela and the Matrix regenerates.
Sam then uses the Matrix to revive Optimus who is surprised, but happy, that Sam came back for him. The Fallen finally shows up and takes the Matrix before Optimus can fully recover, but Jetfire sacrifices himself to give his parts to Optimus and make him more powerful. Sam watches as Optimus kills The Fallen and forces a badly injured Megatron and Starscream to escape, leaving everyone relieved. Simmons and Leo reunite with them, having destroyed the Devastator. On the bow of an aircraft carrier, Optimus joins Sam and thanks him for saving his life. Sam says "You're welcome", and reciprocates by thanking Optimus for believing in him. Sam, Optimus, Mikaela and Leo stand on the bow as Optimus sends out another message.
At some later point, Sam kisses Mikaela goodbye and returns to college where his professor sarcastically refers to him as Professor Einstein and thanks him for rejoining them to which Sam said he's been busy.
Dark of the Moon film
Sam has been dumped by Mikaela, given a Medal of Freedom for his actions in Egypt and now lives with his new girlfriend Carly, Mikaela's former pet ex-Decepticon Wheelie, Brains and his pet dog while Bumblebee no longer lives with him, making him have to use a piece of crap car to get around. Sam doesn't have a job and wants to work with the Autobots, but gets rejected and after his parents show up. He goes to a bunch of job interviews where he is rejected each time until he gets to Accuretta Systems where he meets Bruce Brazos. There, he is offered a job as a mail boy, but wanting to matter again and refuses at first, but Brazos is impressed by him and gives him the job. Sam then meets up with Carly and her boss, Dylan Gould, and becomes jealous of their friendship despite Gould secretly revealing he helped Sam get the job.
Later at work, Sam gets visited by Carly, who now drives an expensive car that Gould gave her, making Sam even more jealous and is asked to a party that Gould is holding. Later, he is accosted by a fellow employee, Jerry Wang, who recognizes him from pictures with the Autobots. Wang scared Sam and gave him a manifesto about the dark side of the Moon. Sam tracked Jerry down, but Jerry acted weird and pretended not to know him, so Sam left. Jerry was killed moments later by Laserbeak who chases Sam through the office before Sam escapes. Sam takes Carly to alert the Autobtos, but is refused entrance to the base until Bumblebee shows up and Sam berates him for not visiting. Sam tells Lennox what happened and gives Jerry's manifesto to him, but is rebuffed by Charlotte Mearing for visiting. Sam then witnesses the revival of Sentinel Prime by Optimus with the Matrix of Leadership. Afterwards, Sam is sent home with Bumblebee for protection.
At home, Sam is dissatified with being brushed off and decides to ask Simmons for help in deciphering the Decepticons plans, getting what Wang was working on from Brazos in exchange for letting him meet Bumblebee. The two figure out that Wang made it so that NASA's probes wouldn't map the dark side of the Moon and that the Decepticons must be hiding something there. Carly arrives to prepare for the party and is mad that Sam is trying to figure out the Decepticons' plans and leaves. Sam and Simmons then head to Atlantic City after Brains discovers two former Soviet cosmonauts hiding there. After a brief standoff, the cosmonauts reveal pictures that show that the Decepticons recovered hundreds of space bridge pillars from the Ark and had hidden them before Apollo 11 arrived. Sam realizes that they needed the Autobots to find and revive Sentinel and need him for their plans to work. With the help of Dino and Sideswipe, Sam and Bumblebee escort Sentinel back to base chased by the Dreads. Along the way, one is killed by Dino and the other two are killed by Ironhide who shows up to help near the base. At the base, Sam can only watch in shock as Sentinel murders Ironhide and retrieves the pillars.
Sam returns home to try to get Carly and after getting advice from his parents, heads to Dylan's party where Dylan reveals himself to be the leader of the Decepticons human collaborators and that his father was responsible for the end of the Apollo program. Dylan uses Soundwave, who has been disguised as Carly's car all along, to force Sam to cooperate and find out the Autobots' plans for the Decepticons through the Watch-bot they place on his wrist.
Sam gets taken to a base where Mearing asks him if he knows anything else and apologizes for underestimating him. Sam is unable to tell her the truth because of the Watch-bot and is shocked to learn that the Autobots are being expelled from the planet. Sam asks Optimus the Autobots plans, secretly signaling him that the Decepticons are listening by telling him no other human will know and Optimus claims they don't have any before leaving after Sam and Bumblebee say a sad goodbye. After Gould calls to confirm what he learned, Sam is forced to watch as the Autobot ship, the Xantium is destroyed with the Autobots.
Sam, wanting to save Carly, has Simmons track the signal from Gould's call and heads to Chicago with Epps and other former NEST members to rescue Carly. They arrive at the city to find it full of Decepticons and Decepticon ships and Epps refuses to head in even though Sam is determined to. The group comes under attack from a Decepticon fighter, but they are saved by Optimus and the other Autobots who escaped the Xantium before its destruction by Starscream. Sam and Bumblebee proceed to use the fighter to travel to Gould's penthouse where Sam tries to rescue Carly, but is attacked by Laserbeak. However, the rescue is a success and Laserbeak is killed by Sam and Bumblebee by using the fighter's guns before the fighter crashes in the street. Using a shot-down UAV, Sam and Carly relay Sentinel's plans to bring Cybertron to Earth.
Needing to stop Sentinel, Sam comes up with the plan to climb a building and use a rocket launcher to shoot down the Control Pillar. With the help of the Autobots, the group makes it close and Que arms them with grappling gloves and boom sticks to use against the Decepticons. They make it into the building, but before they can fire, the Decepticon fighters shoot the building over on its side and they are forced to flee from a Decepticon that enters the building. The group is then nearly killed by the Driller, but Optimus saves them and kills the Driller, allowing them to escape mostly unharmed.
While trying to make it to a bridge to cross the river, they come under attack by Starscream and Sam and Carly get separated from Epps and the others. Starscream is delighted to have the chance to kill Sam and after hiding Carly, Sam shoots a grappling hook into Starscream's right optic, causing Starscream to thrash around and drag Sam with him before he slams Sam through a window into an apartment. NEST attacks Starscream, distracting him and allowing Sam to arm one of his boom sticks, jump on Starscream and stick it into his other optic. Sam gets swung around as Starscream thrashes around even more, but Lennox cuts him free and Bumblebee catches them as the boom stick explodes, decapitating and killing Starscream.
After linking up with NEST and Epps' team near a bridge, Sam is forced to watch as Soundwave prepares to execute Bumblebee after the death of Que. Sam tries to arm another boom stick and help, but the boom stick shorts out. Luckily, Wheelie and Brains cause a distraction (running the largest of drop ships close to their position), allowing Bumblebee to break free and kill Soundwave.
Sam rides with Bumblebee to the site of Optimus' battle with Sentinel after Optimus shoots the Control Pillar down. After hearing Sentinel call for anyone to reactivate it, he heads off to stop anyone who tries. Sam reaches the pillar and fights Gould who reactivates it. Sam proves to be no match for Gould, but manages to hit him with a pole which has a piece of cement attached to it, knocking Gould into the pillar and electrocuting him to death. Sam quickly calls for help and Bumblebee destroys the pillar, stopping the arrival of Cybertron and destroying the planet.
After the battle, Sam reunites with Carly and the two admit they love each other. Bumblebee, trying to help, drops a bunch of rings and plays wedding music, trying to get Sam to propose, but Sam tells him that's taking it too fast.
- First Encounter (Screen Battles, 2007)
- Japanese ID number: SB-01
- This Screen Battles pack features a largely unchanged Deluxe class Barricade figure but the Frenzy accessory has been cast in black plastic to better blend in with Barricade's chest. The pack also comes with unposable figurines of Sam Witwicky in a running pose, Frenzy menacing Sam and Mikaela Banes holding the power saw she uses to attack Frenzy. The set is packaged in a special window box with a diorama depicting the battle between Barricade and Bumblebee.
Revenge of the Fallen
- Bumblebee (Human Alliance, 2009)
- Sam is the human that comes with Bumblebee. He can sit in Bumblebee's seat or in his arm looking like he is firing the guns on his arm. His face has a strange expression much like the one where he started seeing symbols and freaked out. He's a lot more possible than his "First Encounter" version.
- Despite being the main character, Sam Witwicky is a heavily debated subject. Many see him as the reason why the movie was not as good as it could have been due to the fact that first first half of the movie was almost entirely revolved around him, while others see him as a good character (mostly general audiences who haven't had too much experience with Transformers or aren't stuck in G1 like some critics). It is generally accepted that his part was much larger in the movie due to the expense of CGI that it took to make the Transformers.
- Sam was not given the nickname "Spike", nor his father the nickname "Sparkplug" (though his wife does refer to him as "Spark"), because unlike their Generation One counterparts the movie characters are not oil rig workers or mechanics. Earlier drafts of the script did have Sam earning the nickname "Spike" another way, but this was dropped before the script was finalized. 
- Thanks to his brawl with Frenzy, the back of Sam's shirt is ripped, leaving a hole in the back exposing his back. Interestingly, no one points this out to him or even notices during the time he gets a replacement jacket.
- He doesn't masturbate. Especially to issues of Busty Beauties, which he doesn't keep in a treasure chest under his bed.
- Sam's eBay username 'LadiesMan217' is a reference to movie director Michael Bay's birthday, February 17th. If 217 had the same meaning for Sam, that would make his date of birth February 17th, 1990. ladiesman217 is a registered user on eBay, with no items currently for sale.
- In the Japanese dub of the film, Sam's eBay username is changed from "LadiesMan217" to "playboy217", since "ladies' man" isn't a term the Japanese are familiar with; To better suit this joke in the Spanish version, his Username is "DonJuan217", named after the famed Spanish womanizer. In the polish version, his username is translated as "dogforbabies217". In the Spanish version from Spain, his Username is also "LadiesMan217". In the IDW comics adaptation, his ePay username is "hotstud217". This is even more disturbing.
- According to screenwriter Roberto Orci, he and writing partner Alex Kurtzman pitched the character of Sam as "Marty McFly on crack." 
- The junior novel of Revenge of the Fallen implies that Sam has become a Prime in his own right.
- Sam says "SHIT" a lot.
- He also says "no,no,no!" even more times than "$hi7" it would seem! Obviously, he and Megatron would've been the BEST of friends, yessss, this is a staple of most of Shia LaBeouf's characters.
- It can be argued that Sam is one of the most dangerous foes the Decepticons ever faced, as he single handily managed to kill both Megatron, and Starscream, thus depriving the Decepticons of their leader, and second in command. Also, he tends to figure out the Decepticons' plots and how to thwart them, although Optimus does most of the fighting.
- When forced to fight, Sam is not a bad fighter as he single-handedly kills Megatron, Starscream and Dylan Gould with what he has at the time that's deadly. Also, he fought Laserbeak and helped Bumblebee kill him.
- According to the Fallen in Revenge of the Fallen, the AllSpark cannot be destroyed, but only "transform", implying that Sam's brain may have been merged with the AllSpark during the time. After he returns from the death, the effect seems to cease to exist because the Matrix of Leadership absorbed the AllSpark when it reformed.