Peter falls in with Irish gangsters who know about his past. Hiro works to contain the damage caused by his journey into the past. Kensei's power will be revealed. Suresh locates and cures the Haitian. Matt investigates the murder of Mr. Nakamura. West comes to know of Claire's powers. Maya and Alejandro enter Mexico and find their powers more of a hindrance than a help.

Suresh finds an undiscovered Isaac Mendez painting that shows someone's death; Maya frees Alejandro from a Mexican jail; in the past Hiro discovers something new about Kensei; and Niki and Micah leave Las Vegas to get away from their past. Claire and West take a little trip.

A woman named Elle is searching for Peter. Ando looks for Hiro in the past. Matt looks for the man in Molly's dreams. HRG takes another step in hopes of protecting his family and himself.

Peter goes on a search. West convinces Claire to stand up to someone. Hiro struggles with his feelings for Yaeko. Suresh has more problems with the Company. HRG tries to locate more of Isaac's paintings. Alejandro doesn't trust Sylar.

Peter and Caitlin learn about the endstage effects of the Heroes virus. Many of the Heroes work together to fight the Nightmare Man. West is shocked to the identity of Claire's father. Hiro and Kensei's journey comes to an end.

Peter travels to Primatech in Texas to destroy the virus, but not everything is what it seems. Hiro continues the pursuit of his father's killer, while Matt pursues the last Company member in the photo. Nikki is reunited with Micah but has bad news, while Maya has to choose to remain with Alejandro, or go with Sylar.