In the future Claire has turned bad and all those with powers are on the run. Peter confronts Claire and promises her he will prevent Nathan from revealing their existence and undo the past to save her.
Angela confronts her son, Peter. First, Sylar declares war on the Company by attacking their headquarters, and finds a lot more than he expected on Level 5.
Four villains, Knox, Flint, The German and Jesse (with Peter imprisoned inside) break into a bank and take hostages. Angela sends H.R.G. and his new partner, Sylar, in after them.
Peter resolves to prevent an earth-shattering end whatever the cost. He takes on Sylar's dark, unwieldy ability in order to save the world, gambling that the ensuing hunger to kill won't destroy him.
Claire attempts to take down her first target, Stephen Canfield, an escapee with the ability to create black holes. She ends up trying to help him rather than hurt him until Noah intervenes.
Knox and Daphne bring Hiro into the Pinehearst fold, and give him an assignment to bring in Usutu from Africa. With Angela and the Company paralyzed by recent events, Peter goes straight to Pinehearst for some answers.
Nathan and Tracy fight for their lives against Suresh, to free themselves, Maya and the doctor's other "test subjects." Elle returns with her powers out of control and partners with Claire to find out more about Pinehearst.
Through his spirit walk, Hiro follows respected businessman Arthur Petrelli days before he "died," to find out what caused him to create Pinehearst, and also what drove him to strike at Angela.
After a strike against Hiro and Ando in Africa, Arthur Petrelli gets Knox and Flint to look for his son Peter and granddaughter Claire. Nathan is shocked to find out that his father is alive and leading a charge towards worldwide destruction. Meanwhile, Sylar has a charged confrontation with Elle, and Suresh starts testing his new formula. Later, Matt attempts to wake Angela.
After reuniting Sylar and Elle, Arthur orders them to find Claire and bring her to him. Matt, Hiro and Ando team up together and follow Daphne to her hometown of Lawrence, Kansas to discover what she's been hiding. Meanwhile, Nathan and Peter Petrelli travel together to Haiti in search of the only man that can stop their father from destroying the world, the Haitian.
The eclipse continues to impact the Heroes' abilities as Elle and Sylar face off against a vengeful H.R.G. while Claire struggles to survive. In Haiti, Peter and Nathan join forces with the Haitian to battle the Haitian's brother, Baron Samedi, and Nathan comes to a shocking decision. In the meantime, Ando, Sam and Frack work hard to get Hiro's memory back with the help of the "9th Wonders" comic books at a local comic bookstore.