S01E20: 'Five Years Gone'

Set five years in the future in a New York still reeling from the explosion, we see Hiro encounter his future terrorist self, before Matt Parkman - an embittered law enforcer working for Nathan, now President - intervenes and captures the more innocent of the Hiros.

Mohinder is now working as a medical advisor to Nathan, who wants those with special powers to be wiped out.

Niki is back stripping under the guise of Jessica and she has hooked up romantically with Peter, who bears a large scar across his face and still has his powers. It emerges that Micah was killed in the explosion, along with Ando. It emerges that Peter was the cause of the explosion and that Nathan had blamed Sylar to protect his brother.

However, Nathan is in fact Sylar, using Candice's ability to mimic the bodies of other people. Once Claire, who had been tracked down by Parkman, is brought to the President then Sylar unveils himself and cuts open her skull in order to gain her regenerative power - the one he craves the most.

Hiro, after a violent interrogation by Parkman, is ordered to be killed by Nathan, who asks Mohinder to deliver the lethal injection. However, Mohinder fears a genocide of thse with powers and rescues Hiro, injecting the Haitian instead.

Peter joins forces with the terrorist Hiro and Ando to launch an attack on Nathan/Sylar, but the President flies to safety before this can be carried out. Peter tracks down Sylar and they both prepare for battle, with the former generating a nuclear-like fire in his hands whilst the brain-pincher opts for the more icy variety of weapon.

Parkman shoots terrorist Hiro dead, but he gives Ando a part of Isaac's comic before he shuffles his mortal coil. This is witnessed by a rather stunned other Hiro, who manages to teleport him and his friend back five years and to relative safety. The comic depicts him killing Sylar and Hiro prepares to carry out the task in hand...