Our heroes are trying to find ways to cope with recent events. Some (Claire, Matt) trying to find normality and others (Hiro, Ando, Peter) trying to use their abilities to do good. Angela worries about Sylar, and a new threat arrives in the form of a mysterious carnival.
Claire discovers her roommate has been killed. HRG asks Peter to help him and ends up in a difficult situation. Hiro tries to undo his wrongdoing from the past and Matt finally decides to use his powers again.
Peter must face the consequences of his actions and also meets a new female hero. Claire deals with others knowing about her ability. Samuel fights to find his brother Joseph's memories. When Sylar returns, Matt must struggle with his own inner demons.
Hiro's health continues to deteriorate as he goes on a mission to prevent a coworker from committing suicide. Ando finally convinces Hiro to tell his sister that he's fatally ill. Meanwhile, Tracy continues to struggle to find a purpose in life and to learn to control her powers. She returns to her old job as a political adviser, but leaves when she remembers how demeaning the job could be. Nathan-Sylar is also on a path of self-discovery, as his mother, Angela, helps him regain memories.
Lydia cautions Samuel against bringing in new members to their clan. Peter tries to connect with Emma, who wants nothing to do with him, and Sylar struggles to find the person he once was.
Sylar starts to find his true identity. Peter and HRG go on a quest to find someone that can save Hiro.
Sylar continues to torment Matt. HRG and Tracy help a young boy who has suffered many hardships in his life. Claire and Gretchen have a problem with their new sorority sisters hazing them.