Peter Petrelli (Milo Ventimiglia)After regaining his memory and powers, he unwittingly led Adam Monroe to a strain of the virus that could destroy the world. Once he realized he was being played, he managed to stop the outbreak by destroying the vial.

Nathan Petrelli (Adrian Pasdar)The recovering alcoholic (he turned to booze when he thought only he survived Peter's explosion), helped Parkman learn who was killing Company founders. Before he revealed his powers via press conference, he was shot.

Mohinder Suresh (Sendhil Ramamurthy)Working with Noah Bennett, he infiltrated the Company under the guise of testing a cure. However, his motives changed when the virus adapted, and he shot Bennett, who was about to shoot Bob to stop the company.

Noah Bennett (Jack Coleman) Claire's blood brought him back to life, but the Company told his family he was cremated. He shocked them by returning home, but left again, making a painful decision to work for the Company so his family could be left alone.

Claire Bennett (Hayden Panettiere)Angry at the Company for killing her dad, she vowed revenge and threatened to reveal her powers to the world. When flyboy West tried to stop her, their argument led to their breakup, but Noah's return halted her plans.

Matt Parkman (Greg Grunberg)He reunited with his father, but instead of settling daddy issues, he added new depths to his power. Now able to control others' thoughts, he locked daddy inside his fears and investigated the murders of the Company founders.

Hiro Nakamura (Masi Oka)He teleported back to feudal Japan and met Takezo Kensei, who was really the immortal Adam Monroe who later killed Hiro's father. To stop Adam from releasing the virus, he teleported Adam out of the safe, leaving the vial behind.

Adam Monroe (David Anders) He used Peter to break out of the Company's cell, and gained his trust by healing Nathan. He killed Victoria Pratt after learning the location of the virus, but his plan to wipe out the world was thwarted by Hiro and Peter.

Niki Sanders (Ali Larter)She committed herself to the Company for testing, injecting herself with a virus when she lost control of her power. She came for Micah, but while rescuing cousin Monica from a burning building, Niki didn't escape the explosion.

Elle Bishop (Kristen Bell)After being benched by her father for being captured by Noah, Elle decides to impress her dad by bringing in Sylar. When she bursts in on him in Mohinder's lab, he manages to escape with the cure.

Alejandro and Maya Herrera (Shalim Ortiz and Dania Ramirez)They brought Sylar to America after he promised to help Maya get rid of her plague-like power. Sylar killed Alejandro on the trip, and he left Maya with Mohinder when he escaped from the lab.

Sylar (Zachary Quinto)He murdered Alejandro, and taught Maya how to control her own power, an ability he hoped to steal when he was "cured." He escaped Mohinder's lab, injected himself with the cure and regained all his powers, claiming, "I'm back."