Tom Baldwin (Joel Gretsch) is one of the lead NTAC agents responsible for investigating The 4400, along with his partner Diana Skouris. Prior to joining NTAC, he worked as an agent for the FBI. Tom's professional responsibilities sometimes conflict with his personal connections to the 4400.
His nephew Shawn is famous for his healing ability and served as the leader of the 4400 Center, an organization often at odds with NTAC. And his son Kyle spent three years in a coma, a result of trauma he suffered the night Shawn was abducted. The emotional strain from this tragedy hastened the demise of Tom's marriage.
Shawn used his healing ability to awaken Kyle, who subsequently divulged to his father that the 4400 had been taken by the future in order to change history and avert a catastrophe. Moreover, it was Tom's mission to help the 4400 and prevent this bleak future from coming to pass.
While investigating Jordan Collier's assassination, Tom learned his son was the killer and tried to protect him. It was ultimately revealed that Kyle had been inhabited by an entity from the future and wasn't acting on his own accord. Kyle confessed to the murder anyway, and was sent to prison.
Tom sought help from a resurrected Jordan Collier, whose return secured Kyle's release from prison. But Tom's gratitude for Collier's assistance was short-lived. Soon thereafter, Tom found himself hunting a fugitive Collier after he robbed a government facility and distributed its stockpile of promicin. Adding insult to injury, his son Kyle appears to have allied himself with Collier against his father's wishes.
Despite the difficulty of his job, Tom was able to take solace in his relationship with Alana Mareva, a 4400 with the ability to create alternate realities. It was in one of these realities that they met and fell in love.
But Alana betrayed Tom by tipping off a fellow 4400 that NTAC was closing in, and she was forced to flee Seattle in order to avoid prosecution. The two were later reunited, but soon after Alana mysteriously disappeared. Tom has spent months searching for her, but with no leads to go on he's nearly given up hope.
The "evil" Tom takes Isabelle to a secluded beach house and convinces her to fulfill her original mission of destroying the 4400. First, he rids her of the anti-promicin allergens that the government gave her. Then, he sends her back into Promise City with the warning that if she tries anything funny, he can activate the newly installed "kill switch" and she will die.
Meanwhile, Tom tries to act normally. He and Diana try to find the source of a computer virus that is disrupting ATM's and causing computer failures all over the country. With the help of Marco, they trace the disruptions to Warren Trask, a man who was swindled by Drew Imroth, the head of Ubient. Even though on life support, Trask has used his ability to go into the internet and disrupt it from inside.
Because of all the disruptions, Drew Imroth's Ubient is about to go bankrupt. Tom attempts to solve the problem by driving an SUV into a telephone poll near Trask's home, thus knocking out power to Trask's life support and killing him. Later, Tom tells the man inhabiting Imroth to get out so he can inhabit the body of Jordan Collier.
Meanwhile, Diana and Meghan have figured out that Tom is marked and that someone else is inside him.
Tom begins to have memories that are not his, and he realizes that someone or something is inside him. One of his disturbing visions is of himself surgically impregnating Lily Tyler in the future.
Rebecca Parrish, the director of National Intelligence, visits NTAC and tells Tom and Diana that she is not happy with the way things are going in Seattle. She orders them to find Richard Tyler and bring him back to NTAC.
Later, Parrish confronts Tom and tells him that if he feels like someone is inside him, he should stop fighting it and just relax. The next morning, Tom finally gives in and he is now one of the Marked.
Parrish meets with the "new" Tom and warns him not to blow his cover. She suggests that he do what the old Tom would do: find Richard and Isabelle Tyler. Tom does just this, when he and Diana go to a house and find Richard, Isabelle, and Cora hiding out. Tom shoots Richard and Cora with a tranquilizer gun and secretly takes Isabelle back to his house.
Tom awakes to find himself trapped at NTAC with many of his co-workers as well as Collier, Kyle, and Isabelle. Eventually, theory room geek PJ confesses that it is all a game. After taking the shot, PJ developed an ability where he selects players and then the game begins in a shared psychic space. In the game, the players have to work together to overcome an obstacle. In this case, the obstacle is NTAC itself. When the building kills off Meghan, Shawn, and PJ, Collier and Tom join forces, however briefly, and save everyone by short circuiting the building.
After Tom wakes up after the game, he calls Collier. Collier says that just because they cooperated in the dream, nothing is going to change. He will still build Promise City and hand out promicin to anyone who wants it.
Maia has a vision that leads NTAC to Promise City. When U.S. soldiers plan to invade, Tom warns Kyle to get out, but Kyle demurs. Kyle tells his father about his ability and his new role in Collier's revolution.
Marco informs Tom and Diana that a 4400 named Curtis Peck has disappeared. Peck's ability is to use his filmmaking skills—or lack thereof—to reveal the truth about conspiracies. Peck's latest conspiracy involves the Marked, people who've come back from the future and implanted their consciousness into ten prominent people in order to stop Jordan Collier.
After tracking down Peck, Tom and Diana discover that Drew Imroth, the CEO of Ubient software, is one of the marked. When Tom and Diana confront Imroth, he denies any knowledge of this strange theory, even though inspection reveals he does have a mark behind his ear.
Soon after, federal forces take Tom to a psychiatric evaluation center. While there, they inject him with something. Tom wakes up with a suspicious mark behind his ear.
After finding out that Kyle has an ability, Tom goes on the road to find him. Tom ends up in sleepy Evanston, where he discovers a town full of inhabitants with abilities.
Soon, Collier discovers Tom's presence there and confronts him. Collier tells Tom that Kyle is now a part of his movement. When Tom asks about Evanston, Collier tells him it's "a model for a better world."
Kyle finally meets with Tom and urges him to take promicin and join the cause. Tom tells Kyle this isn't possible because promicin is not only dangerous, it's illegal. Kyle considers giving his father the shot against his will, but backs down. Instead, Collier gives Tom a sedative. When he wakes up, Tom finds nothing but empty streets and abandoned houses. Later, Tom is tested for promicin but the results come back negative.
Meghan suggests to Tom that Kyle is probably the one responsible for giving Shawn a dose of promicin. Tom then confronts Kyle about it but Kyle flatly denies the charge. Determined to get the truth, Tom secures a hair from Kyle's hairbrush to bring in for testing.
Meanwhile, Tom and Diana discover that April has taken promicin and developed the ability to make people answer her questions truthfully. When April gets embroiled in a corporate conspiracy, Tom and Diana partner help her get out of the mess.
Later, Marco confirms to Tom that Kyle's hair tested positive for promicin.
Meghan tells Tom and Diana to find Audrey Parker, an elderly woman who is blogging about how promicin changed her life. When Audrey quotes Benjamin Franklin in her blog, Tom and Diana realize it is a woman they'd previously met at the library. But by the time they go to see her, she is dead. However, Audrey's astral projection is able to communicate through radio static. She uses this method to tell Tom and Diana that her nurse's son was the one who killer her.
When Tom finds out how distraught Meghan is over her father's deteriorating health, he offers to talk to Shawn about it.
When Shawn reopens the Center, Tom convinces the national guardsmen that if they fire into the crowd, they will lose the hearts and minds of the American people. It works; the national guard allows Shawn to carry on.
Doctor Clayton informs Tom and Garrity that someone or some thing is making people hallucinate about their worst fears. After some sleuthing, Tom and Garrity discover that a man named Ryan Preston gave his son Brandon a dose of Promicin in an attempt to cure his autism. Not only did it not cure the autism, the Promicin gave Brandon a very dangerous ability. When Garrity is hospitalized after upsetting the boy, Diana and Tom partner up to track down the boy and his mother. When they do find Brandon, Tom sedates him. Back at NTAC, Shawn is able to heal the boy, ridding him of his autism.
Meghan visits Tom at the museum and tells him that Garrity will be well soon. Tom praises Garrity, but tells Meghan that he'd rather partner with Diana. Later, Tom takes down the pictures of Alana that he has been obsessing over for months.
Tom is surprised but happy when Kyle moves back home.
Later he meets the new head of NTAC, Meghan Doyle. She tells Tom that Isabelle may have some information regarding the disappearance of Alana Mareva. Whe Tom goes to visit Isabelle, she passes him a note that urges him to check out a particular gallery at the Powell Museum of Art. There, Tom sees a painting of a woman that looks exactly like Alana, dated 1885.
Along with Garrity and the others at NTAC, Tom sets out to stop Graham Holt, a student who takes promicin and becomes a spiritual leader with hordes of followers. As Holt converts more and more people to worship him, including the police and some at NTAC, it is actually Collier, not Tom, who stops Graham.
SEASONS ONE-THREE TIMELINE
Dennis Ryland brings Tom back to NTAC and pairs him with Diana in order to lead the investigation into The 4400. Tom's nephew, Shawn Farrell, is one of the returnees.
Rather than welcome Shawn back with open arms, Tom interrogates Shawn on what happened the night he was abducted -- the night Tom's son, Kyle, fell into a coma that's lasted three years. Tom soon discovers Shawn has brought Kyle out of his coma and although grateful, Tom is confused by Shawn's abilities and his son's strange new behavior.
Later Tom accompanies Kyle to Highland Beach. It's clear that Kyle is not actually Kyle. While at the beach, a beam of light releases from Kyle's chest, allowing Tom to interact with the future beings. The future informs Tom that The 4400 have been sent back to save humanity and re-write history.
Tom wakes one morning, long after the return of The 4400, to find his life suddenly an idyllic one. Other than himself, no one has heard of The 4400. Kyle is an honors student at Standford Medical College. Tom is married again ... to Alana Mareva, a beautiful art gallery curator. Alana confides in Tom that she too has heard of The 4400 and that she is in fact one of them. Soon the two learn they are living in an alternative reality created by Alana based upon their individual memories. Alan and Tom begin an eight-year marriage in this alternate universe. Upon returning to reality they choose to continue their relationship and try to integrate Tom's son Kyle into their new life.
After Jordan Collier's assassination, Tom's son is found missing. In an effort to find him, Alana and Tom investigate a locker Kyle rented and discover its contents: a gun and a newspaper article on Jordan Collier -- evidence of Kyle's involvement in the murder.
The 4400 begin to grow sick and all of them, sick or not, are quarantined. Tom and Diana begin to investigate. They soon discover that NTAC is behind the deathly illness and Diana correctly predicts that Ryland engineered the entire thing. When Tom confronts Ryland, he blackmails him -- Ryland knows Kyle is responsible for Collier's murder.
After Tom finally tracks him down, Kyle agrees to confess to the murder, freeing Tom to expose NTAC's role in the scandal.
NTAC receives a message from a radical wing of the 4400 known as the NOVA group. The group promises that something drastic will happen on October 19th. Tom and Diana are assigned to investigate.
Using 4400 Gary Navarro, Tom and Diana begin to hunt down the members of the NOVA group. Little does Tom know, Gary is purposely leading them in the wrong direction.
Tom and Diana discover Gary's lies before he murders Ryland. During Gary's interrogation they learn he is working for Daniel Armand and NOVA.
With the help of Shawn, Tom and Diana arrest NOVA member TJ Kim and prepare for the events of October 19th. But what they expect to be a disaster instead turns into a miracle. The NOVA group is warning the world – they can use their powers for good or for evil.
Tom is shocked to learn that Alana plans to teach at The 4400 Center School and use her abilities with the children.
When Tom and Diana are both haunted by visions of a strange young girl, they realize the girl is Diana's daughter Maia, erased from their lives by the future. The future agrees to return Maia as long as Tom kills Isabelle.
Before killing Isabelle, vows to find out more before he can make his final decision.
When Tom and Diana arrive at Gary Navarro's house they are surprised to find him missing and surmise that someone tipped him off. Tom is shocked and betrayed when he learns that it was, in fact, his wife Alana who warned Gary. After Alana is taken into custody, Tom does everything in his power to find Gary, convinced that Dennis Ryland will be willing to trade Alana for Gary. But Tom and Diana can't follow through with the plan and instead release both Gary and Alana explaining they'll have to live a life on the run. Faced with no other choice, Tom watches Alana walk out of his life.
After receiving an anonymous package of cookies, Tom begins seeing his dead father and realizes that the cookies were laced with a hallucinogen called Blink.
When Kevin Burkhoff goes missing, Tom helps Diana begin the search. But when Diana is kidnapped by Kevin (in an effort to continue his promicin experiments on her), Tom must work with NTAC to find his partner. Although Tom finds Diana before it's too late, Kevin and Tess manage to escape.
Diana and Tom discoverer the Starzl Mutation, a rare abnormality seen only in 123 people in the Seattle area. It turns out that the only way 4400's can have children with abilities is to reproduce with someone with the Starzl Mutation.
Tom learns that Haspel Corp has been injecting participants in an enhanced soldier program with promicin to create an army with 4400 abilities. Although unnerved by this information, Tom heads to the Center for his nephew's wedding.
Tom finds out that Jordan Collier is alive but has no memory. With Alana's help, Jordan regains his memory and Kyle is released from prison.
Tom is shocked when Kyle explains that instead of heading back to college, he's leaving to help the 4400 in any way he can.
Meanwhile at work, after NOVA members manage to escape from NTAC, Tom and Diana attempt to avoid a confrontation between Collier/the 4400 and Ryland/his enhanced army. Along the way, Tom learns that Isabelle has been working with Ryland but more astonishingly, that Collier was able to steal Ryland's entire supply of promicin. Together with Diana, Tom worries about what Collier will do with his new stock of the promicin.
After learning that someone plans on distributing promicin publicly, Tom and Diana suspect Collier is behind it all. When Tom and Diana discover Shawn trying to heal a dying Devon, he is brought into NTAC and although Tom tries to get information out of his nephew he is unsuccessful. But Tom soon learns that Isabelle plans to take down the 4400 Center and heads to intercept her. When Isabelle manages to overpower Tom, he fears for his life, until Richard arrives and injects Isabelle with the white syringe. Fearing, however that Isabelle may still have abilities, Tom empties a round into her arm, testing her ability to heal. With the problem of Collier and the 4400 momentarily behind him, Tom says goodbye to Diana and Maia as they prepare to leave for Spain.