
http://en.wikipedia.org/wiki/Heroes_(TV_series)
Claire Bennet (“The cheerleader”)

Ability: Regeneration – she can heal from any wound almost instantly, she can’t be killed
Relations: Raised by Noah Bennet but her biological father is Nathan Petrelli, niece of Peter Petrelli and granddaughter of Angela Petrelli
About: Claire is definitely the main character in the show throughout the four seasons. The other characters are always there to help her, rescue her, battle with her, etc. She is a strong willed character who stands by her principles and always tries to help those around her. She struggles with her father (Noah) and their relationship is a recurring theme of the show. Claire is a great character and the show did an excellent job casting her!
Noah Bennet

Ability: No special abilities but excellent at tracking “specials” and protecting Claire
Relations: Adopted father to Claire Bennet, long time working relationship with Angela Petrelli
About: Noah starts off in a seemingly antagonistic role but gradually we see that he is doing everything he can to protect his daughter Claire. We don’t find out until the end of the show but Noah’s first wife was murdered by a man with telekinesis and this prompted him to start tracking down people with abilities. “The Company” then recruited him to help them track down people with abilities, monitor them and capture any dangerous ones. Years later, he is forced to adopt a baby (“Claire”) as an assignment but he loves her as his own daughter and will do anything to protect her. Noah could be described as ruthless and he doesn’t always make the best decisions (and he has a habit of lying) so his relationship with his family is a constant struggle. But Noah always has a plan, and is always one step ahead of the bad guys in the fight to keep Claire safe.
Peter Petrelli

Abilities: Peter adopts the abilities of other specials by touching them. Initially his powers work like a sponge and he keeps accumulating powers (flying, telekinesis, mind reading and mind control, nuclear reactions, invisibility, super strength and speed, self regeneration, etc) but after some events that take place mid-way through the show, he is only able to keep one power at a time (he retains the power of whoever he touched last)
Relations: Brother of Nathan Petrelli, Son of Angela Petrelli, Uncle of Claire Bennet
About: Peter is an empath, he can take on the powers of others around him. Of course he is also a very empathetic character with strong beliefs about right and wrong. Peter will do anything to protect his family, especially Claire and his brother Nathan. Peter and Nathan’s relationship through the show is a constant struggle (brothers never agree on anything) but they always forgive each other for any wrongdoings.
Hiro Nakamura & Ando Mashashi

Abilities: Hiro is the master of time and space – he can freeze time and teleport to any time or place. For most of the show Ando has no ability, but eventually he gains an ability that can supercharge others’ abilities.
Relations: Hiro and Ando are best friends and worked together in Japan. Hiro’s father is a founding member of “The Company” (and is the person who forced Noah to adopt Claire). Ando is also in love with Hiro’s sister.
About: I put these two characters together because one would not be the same without the other. Hiro is dedicated to his missions and wants to bring peace and justice to the world. Ando is his faithful best friend who follows him on all these adventures and looks out for him. These two are also the plucky comic relief in the show. Their characters can be serious but one of them is always teasing the other or playing a trick on him. The ability to travel through time and space allows these two (especially Hiro) to interact with pretty much every other character in the show at some point. Hiro and Ando struggle with determining when to go back and change the past or when things are as destiny intended.
Gabriel Gray (Sylar)

Abilities: His only true ability is to understand how things work and how to fix things that are broken. However, this ability drives him to “collect” other people’s abilities by killing them and removing the ability from their brain. Eventually he obtains more powers than I can even remember: telekinesis, freezing, perfect memory, liquification, super hearing, precognition (can paint or draw the future), radioactivity, self regeneration, lie detection, electric manipulation, shape shifting, disintegration, flying, and knowing the history of any object he touches.
Relations: At one point we are led to believe that Sylar is the son of Angela Petrelli but we eventually find out that his father has the same abilities as he does and his father murdered his mother when Sylar was a child. Sylar was raised by a watchmaker and his wife who were related to Sylar’s biological father.
About: Sylar is the clear antagonist of the show – he is driven to hunt down and kill as many people with abilities as possible. His motivations seem to vary but he mostly wants to collect the abilities of everyone so that he is the most powerful person alive. Eventually, we see Sylar start to question his own murders (especially after he accidentally kills his own mother) and he starts to wonder what he really wants. The show ends with a drastic turn-around for Sylar where he finally feels remorse for all the killings and wishes to have his powers removed so that he is no longer tempted to use them for evil. While his powers aren’t removed, he seems determined to be a good person in the future (we also got glimpses of a future that implied that he one day marries Claire and has a son with her named “Noah” after Claire’s father). The best part about Sylar as the antagonist is that he is extremely charismatic, people he meets for the first time never fear him. They usually trust him immediately and welcome him in with open arms only to find out too late that he is the one they should be running from.
Nathan Petrelli

Abilities: Flying
Relations: Son of Angela Petrelli, brother of Peter Petrelli and biological father of Claire Bennet
About: Nathan is a US Senator who is a good person but is easily manipulated by those around him (especially his mother and father). His brother is the most important person to him and he loves him very much (even though he doesn’t always treat his brother the best or listen to his opinions). Nathan makes many mistakes throughout the show but always realizes it eventually and tries to right the wrongs he’s done. At first Nathan and Claire don’t get along well because Nathan didn’t know about Claire and didn’t want her to ruin his political career but eventually they both grow to respect each other.
Matt Parkman

Abilities: Mind reading – but he can also push thoughts into people’s heads (think “Star Wars”) and create illusions so that people see something entirely different from reality
Relations: No direct tie to the other main characters other than friendships and circumstances but he does eventually have a son (also named Matt Parkman) who can control electronics (Hiro calls him “baby touch and go”)
About: Matt starts off as a cop who has a hard time but is constantly trying to improve his situations. He struggles with his wife and his job as he learns about this ability. Matt is constantly being recruited by Noah, Angela and the others to help them with things but Matt really just wants to be left alone to live with and protect his wife and son. He is very powerful but his powers often come with side effects or consequences (like when he tries to erase Sylar’s memories but instead ends up with Sylar’s personality also living inside his own head)
Dr. Mohinder Suresh

Ability: Initially none, then he turns into a crazy murderous lizard after an experiment gone wrong (like Dr. Jekyll and Mr. Hyde) and then turns back into himself except with super strength
Relations: His father (Dr. Chandra Suresh) was one of the first people to discover that there were people with superhuman abilities. His father was involved with the first experiments on people with abilities – he had good intentions but his actions are what led to the formation of “The company”. His father’s experiment group included Angela Petrelli.
About: After Mohinder’s father was murdered, Mohinder moved to the US just to find out what happened to his father and possibly take revenge. But he becomes obsessed with his father’s research and picks up where his father left off – trying to locate and help people with abilities. Mohinder is good-hearted and wants to help people but he also secretly wanted to have abilities of his own and was led astray in his quest to obtain his own abilities. By the end of the show, Mohinder (like Parkman) just wants to be left out of the drama to live a simple life teaching in India (but he always gets drawn back into his father’s work).
Angela Petrelli

Ability: Dreams the future
Relations: Mother of Nathan and Peter Petrelli, Grandmother of Claire Bennet, long-time associate of Noah Bennet
About: Angela is a very troubled character who spends most of the show scheming and manipulating those around her. She seems to think she is doing what’s best but her ideas and plans can be very disturbing. She loves her two sons but she uses them to accomplish what she wants to and lies to them constantly. Claire was instantly suspicious of her upon their meeting and could see what Angela was doing – hence the relationship between them was pretty rocky. Towards the end of the show we start to learn more about Angela’s past and what made her act the way she does.
Other Characters
The Haitian (played by Jimmy Jean-Louis): A special who works for the company and is a friend and ally of Noah Bennet. He rarely speaks and many people think he is mute because of it. He has two unique abilities: he can erase memories and when other specials are around him, their powers don’t work. Both of these abilities are vital to the company and to Claire’s protection. We see him many times throughout the show and he’s always there to help when needed.
Isaac Mendez (played by Santiago Cabrera): A painter who can see/paint the future and brings the characters together when he paints a picture of Claire being attacked and then of New York City exploding. Much of season 1 is based around “Save the cheerleader, save the world” which comes from Issac’s paintings.
Niki /Jessica Sanders (played by Ali Larter), DJ, and Micah Sanders (played by Noah Gray-Cabey): These three characters make up a very troubled family in season one. Niki’s husband is in jail for a big robbery and killing his accomplices but he claims he was set up. We quickly learn that Niki has an alternate personality and that her other half is very dangerous. Niki/Jessica also have super strength but Niki doesn’t know she is strong as well, she thinks only Jessica is strong. Their son Micah develops a talent for controlling computers – he can make lights turn green, make the atm give him all the cash he wants or use someone’s cell phone to locate them (just by asking the computer for what he wants). Micah also makes some appearances later in the show as “rebel”, an unknown special who is helping others escape from government agents who have been hunting them down
Adam Monroe/Takezo Kensei (played by David Anders): Adam is a regen like Claire but through him we find out that people who regen can live forever. He also has an interesting storyline with Hiro who he meets when Hiro accidentally time travels to the 16th century
Elle Bishop (played by Kristen Bell): Like Claire, Elle’s father worked for the company all his life. Except Elle’s father wasn’t doing it to protect her, Elle is a psychological mess who eventually turns to Claire for help but winds up dead after a romantic fling with Sylar.
Samuel Sullivan (played by Robert Knepper): True to his usual form, Robert Knepper plays a creepy and disturbed character. He operates a carnival where “specials” can live free from detection. He advertises his carnival as a safe haven but in reality he is collecting “specials” to increase his power and attempt to overthrow the human world.
Emma Coolidge (played by Deanne Bray): Emma plays a deaf file clerk who finds out she can “see” sounds and she can also play a siren song – when she plays an instrument people are drawn to her. The show definitely implied that her and Peter Petrelli could have a future relationship (if the show didn’t get canceled).
Traci Strauss (played by Ali Larter): After Niki Sanders gets killed off, the show still wanted to keep actress Ali Larter so they created Traci Strause (supposedly Niki’s triplet sister she never knew about). Traci can freeze things instantly and is mostly a protagonist – but she used to be a lobbyist so she knows what needs to be done to save her own skin.