Matt Parkman is a police officer with the LAPD. He tried to become a detective, but has flunked the exam three times due to dyslexia. Parkman is a mind-reader; he can hear the thoughts of people around him. He first realizes this after hearing the thoughts of Molly Walker, a girl who was hiding from a serial killer named Sylar. Not able to explain how he knew where Molly was hiding, Matt is arrested.
After proving his ability to his FBI partner by reading her thoughts, he is offered a position in the investigation. Things turn dangerous when a man who appears to be Sylar shows up. Stopping the man from harming Molly, Matt tries to comfort her while Audrey, the FBI agent, gives chase. Ultimately, the man escapes, but not before displaying apparent telekinesis and standing after being shot. Later, Matt comes home to his wife, Janice, with whom he is going to couples therapy.
Matt escapes to a bar after a heated argument with his wife and hears the thoughts of the various patrons. However, when he encounters a patron, a tall silent black man, whose mind he cannot read, the other voices fade out. The man sits and stares at Matt until Matt falls unconscious.
Matt wakes up strapped to a table with Mr. Bennet standing over him. Bennet explains that they had to drug him, and that he works for a secret company. Matt tries to read Bennet's mind, but is unable to due to the Haitian, who was the man at the bar. Matt is still able to discern the name of Bennet's daughter, Claire, impressing Bennet with his developing power. The Haitian then wipes Matt's memories of being drugged and abducted by Bennet.
Matt wakes up a day later, suffering from what he thinks is a hangover. His wife Janice tells him he has been missing and was worried. He uses his ability to listen to her thoughts and give her everything she wants, healing the rift between the two of them.
The following day at work, Matt and his partner at the FBI run down a possible lead on Sylar after discovering a charred corpse with a fingerprint. Instead of Sylar, they find a man with radioactive powers. In a stand off, Matt defuses the situation by allowing the man to speak with his comatose wife. At the end of the day, Matt is informed by his old partner that he was being given another chance to apply for a detective position. Matt reads the man's mind, discovering that he is sleeping with Janice. Matt punches his former partner and is consequently suspended.
Unaware of this, Audrey asks Matt for assistance in interviewing Ted Sprague, the man who radiates nuclear power. Matt talks with him and discovers that, like himself, Ted was abducted from a bar after seeing the Haitian and woke up later with amnesia. He further discovers similar marks on their necks. Then, Homeland Security takes Ted into custody before Matt can learn more, but Ted tells Matt to "find the Haitian." Audrey later notifies Matt that Ted has escaped.
Matt and Audrey then investigate a crime scene at Union Wells High in Peter Petrelli a suspect in Jackie's death, but interrogate him and learn that Sylar's target was the cheerleader Claire.
Matt later attempts to read Claire Bennet's mind when she is being interviewed. However, he is unable to hear anything except static, which also happened to him before he was abducted. Suspicious, he and Audrey stake out Primatech Paper and Matt recognizes The Haitian. He attempts to overhear Mr. Bennet or the Haitian's thoughts and is able to pick up just one word: "Sylar."
For the next two weeks, Matt keeps a close watch on Primatech Paper, but he is seen on cameras. Finally, in "Aron Malsky, a man who stole $2 million from Jessica comes to kill Aron for Linderman. After a fight, Jessica throws Matt out of a window and onto a sign girder; then proceeded to tear Aron in half. Malsky had hidden diamonds in the ceiling shortly before he died. Matt finds them and keeps them.
In "Hana Gitelman. Hana informs Matt of Primatech and the connection to their abductions and the markings on their necks. Ted wants to confront Mr. Bennet, but needs Matt's help. Matt agrees. Both Matt and Ted confront Mr. Bennet and his family at gunpoint as the family was coming home. However, things turn sour and Matt is soon captured again.
In "The Hard Part", Matt, Bennet and Ted continue their mission. They later are shown walking at Kirby Plaza in New York City, where Bennet and Claire are reunited. The group then splits in two, with Peter, Claire and Ted going to a remote town in Nebraska, and Matt and Bennet continuing with their mission to destroy the tracking system. Matt gets them where they need to go.
While waiting for the elevator, they bump into Jessica and her husband, D.L. Bennet and Matt then go to where the tracking system is, only to find Thompson waiting. Matt saves Bennet from death, and Bennet kills Thompson. The two then find the tracking system, surprised to find Molly Walker. Matt protests killing her, but Bennet says it must be done. They argue with Bennet until Matt is knocked out by Mohinder from behind.
In the finale, "How to Stop an Exploding Man", Matt finds Sylar and shoots him. However, Sylar reverses the bullets and gravely wounds Matt. He is brought to a hospital, upsetting Molly.
In "Four Months Later…," it is revealed Matt divorced Janice and that he is now a detective for the NYPD, and is taking care of Molly Walker in Mohinder's apartment. He learns Molly is having nightmares of a dangerous man who can see her when she thinks of him. In "Lizards", Matt is investigating the murder of Kaito Nakamura. He interrogates Angela Petrelli and learns that someone may have murdered Kaito for revenge; but Angela refuses to be interrogated further. Matt later saves Angela from a mysterious attacker. In "The Kindness of Strangers, Matt finds out that his father is part of The Company and that he is the dangerous man frightening Molly. However, Molly tries to find him for Matt, but she ends up in a coma.
In "Fight or Flight" Matt and Nathan track down Matt's father. When they find him, he reveals he is also a telepath, and is also about to be murdered. At first he seems sorry for having left Matt as a child but ends up tricking Matt and Nathan in separate illusions. Matt is trapped in jail, confronted by his ex-wife and the baby she gave birth to after the divorce. It is indicated that while she said that the baby she was having wasn't Matt's, he knew that this wasn't true. Matt is able to telepathically talk to Nathan and escape the illusion, finding that Bob is set to be killed.
In "Out of Time", Matt discovers he is able to manipulate people and uses it to find the last unknown survivor of the photograph by "interrogating" Angela Petrelli. He also finally defeats his father because he learns that like his father he is able to control all aspects of the brain. He manages to tap into this and enter the nightmare Molly's trapped in and summon his father into it. He realizes it's his father's own nightmare and after a battle of wills leaves it with Molly and uses his powers to trap his father in his own nightmare. In "Powerless", he goes with Nathan to intercept Peter and Adam Monroe, in hopes of stopping them from releasing a deadly virus that would kill 93% of the world's population. Before leaving to confront them, Angela warns Matt that if they cannot stop Peter, that he'll have to kill him. Upon meeting Peter at Primatech, Matt attempts to compel Peter to stop Adam. Though this proves unsuccessful, Nathan is later able to convince Peter that Adam has tricked him. Together, they manage to stop the virus, and resolve to reveal their secret, and the Company, to the world. Nathan enlists Matt's help to use his powers in convincing the media to hear him out. At the conference, Matt is present when Nathan is gunned down before he can reveal their secrets, but is unable to locate the assailant immediately after the attack.
In "The Second Coming", after Nathan is shot, Matt and Peter chase the assailant, a future version of Peter, finding nothing. Matt later confronts the future Peter, who is disguised as his present self, when he becomes suspicious of his actions. Future Peter then removes his disguise, confesses that he is from the future and shot Nathan, and teleports Matt to an unknown location in Africa, because he knows too much. In "The Butterfly Effect", he is rescued by Usutu, who paints the future, particularly Parkman's life. He learns Parkman's name by reading it off his badge.
In "I Am Become Death", Matt sees the future through a dream caused by Usutu. In the dream, he finds himself still living with Molly in the same apartment as he did in the second season, only this time accompanied with another daughter, called Daniella, and the baby's mother, Daphne. Matt expresses his concern of Daphne still working for Pinehearst when she comes by to ask Molly where the present Peter fled to. Matt is next seen in awed silence watching a news report on the nuclear explosion in Costa Verde (caused by Sylar), with Molly, worried that Daphne was caught in the blast. Daphne arrives home seconds later with a smile, but gasps that she wasn't fast enough before collapsing in Matt's arms. Matt then wakes up to realize that he never left Usutu or the desert, and realizes that he must find Daphne to keep her from suffering the same fate she did in his dream. Usutu tells him that only Matt can find his way, and that he must follow his spirit guide. Matt is confused, but then notices the tortoise he saw right before meeting Usutu, and realizes it is his spirit guide. He is then seen following the tortoise as it moves slowly through the desert.
In "Dying of the Light", Matt has arrived at an airport with the tortoise. He is greeted by Daphne, who is shocked that he knows her name. He tells her that they are soulmates, which she doesn't believe, instead offering him a job at Pinehearst. She tells him to wait for her. After awhile he decides to go ahead and leave. Daphne returns in time to stop him. She says he's a good guy and the people at Pinehearst aren't. She advises him to stay away. He tells her she should keep away from them as well. She tells him that she can't and leaves.
In "Eris Quod Sum", Daphne is directed by Arthur Petrelli to kill Matt after he does not come to Pinehearst. She has the gun pointed at Matt, but drops it. Knox, however, has followed her, and after knocking Daphne unconscious rips his hand through Matt, apparently killing him. After he leaves, this proves to be a dream sequence manifested by Matt. However soon after this Daphne receives a call from Arthur revealing that she is fooling Matt into trusting her for an unknown purpose.
In "It's Coming" he and Daphne go to Primatech for help and find Angela in a coma. Matt decides to use his powers to try and wake her up. After Daphne supposedly goes to find a nurse but in reality alerts Arthur to his plans, Matt enters Angela's mind like he entered Molly's to save her from Maury. In Angela's mind he finds her handcuffed to a chair and she tells him to leave as Arthur is too powerful. As he tries to free her Arthur shows up disguised as Daphne and stabs him. When this wound manifests physically, the real Daphne grabs on to him and manages to get him to pull her into Angela's mind. Once there Arthur reveals that Daphne had betrayed him, but while Daphne admits this, she repents saying she loves Matt and the two embrace. Angela manages to convince Arthur to let her go and Matt pulls himself, Daphne and Angela back to the real world, finally waking her up. His psychic wound heals at this point. He then encounters Peter and attacks him for sending Matt to Africa, but Peter is able to convince him, after Matt verifies telepathically, that it wasn't him. Matt is present when Angela reveals that there's a catalyst needed for the formula and Claire realizes that it could be her.
 Alternate futures
- In the alternate future of "Five Years Gone", in which New York City is destroyed by a nuclear explosion, Matt is seen working as Director of the Department of Homeland Security and is in direct contact with the now President Nathan Petrelli (who is actually Sylar in disguise). In this future Matt is seen as being a much darker and cynical man who hunts down those with abilities and arrests them. He kills Hana Gitelman, Mr. Bennet and Future Hiro. At the end of the episode, he is shocked to find that Sylar had been using his powers to disguise himself as Nathan. He still cares about his family however and has a much greater deal of control over his powers, being able to "rip out" memories instead of passively overhearing thoughts.
- In the alternate future of "I Am Become Death", in which abilities are publicly available, Matt is living with his adoptive daughter Molly, his wife Daphne, and his own infant daughter. He attempts to talk his wife out of tracking down Peter. He watches Daphne die in his arms when she returns after trying to escape the nuclear explosion in Costa Verde.
 Powers and abilities
Matt is a telepath, able to read and manipulate the thoughts of others. In the episode "Out of Time", Bob states that Matt, like his father, should be able to control all aspects of the mind, including thoughts and senses, with practice. Matt originally could not activate his at will, causing him to pick up the thoughts of all those in close proximity to him. He gradually learns to elicit specific thoughts from people, and eventually learns to compel individuals to do as he wishes.
Though Matt's power enables him to read the minds of most people, it can be defeated through various methods. The Haitian's power is able to nullify Matt's, protecting himself and those in his vicinity. Other telepaths, such as Peter Petrelli and Maury Parkman, are also able to shield their minds. Finally, since Matt only speaks English, he cannot understand thoughts in other languages; Noah Bennet is able to defeat Matt's power by thinking in Japanese.
Matt's ability to compel others is not as honed as his father's, though he demonstrates the ability at various points. He is able to enter the minds of various individuals in different episodes, including Nathan Petrelli, Molly Walker, and Angela Petrelli. When Maury traps Matt inside Molly's "nightmare world", Matt is able to bring his father in with them and subsequently leave with Molly, trapping Maury in his own nightmare (though Maury escapes). Matt can place suggestions in others through telepathic commands as a form of mind control, but those aware of what he is doing can resist. In "Cautionary Tales", Angela Petrelli initially resists his commands, though she experiences a nosebleed and eventually succumbs. In "Eris Quod Sum", Matt is able to make the villain Knox see an illusion of Matt himself dying, as well as momentarily immobilize him physically.