Outside forces and new faces drive the "Heroes" into different directions.

Claire finds it increasingly difficult to keep lying to her father, all the while knowing exactly what has happened all around her, while she makes plans to visit her biological mother. Nikki's husband makes a deal for her release. Hiro's father wants him to return to Japan, and he scrambles to find a way to stay his own course, searching for the sword. Peter convinces Claude to help him understand his own powers, including Claude's invisibility.

H.R.G.'s past catches up to him as Matt and Ted Sprague come to Texas looking for answers, and take him, his wife, son and Claire hostage -- leading to a tragic, explosive showdown.

Peter feels the need to control his newly absorbed power, as he overhears Sylar's thoughts on the streets of New York. Mohinder finds another hero and agrees to help find a cure for her fatal disease, as Parkman and Bennet close in on the building they are in, looking for a link that could set them free. Niki/Jessica and D.L. are convinced that Linderman is behind their son's disappearance, as Linderman convinces their son to do a job for him.

Can Sylar be stopped? Will Linderman's vision live on with Nathan? What will it take for Peter to save the world, what sacrifices will be made? With all the horrible predictions unfolding before them the heroes face moments of pain and peril in Kirby Plaza.

Four months after the events of Peter's explosion, we find the heroes at different places in their lives. Claire, HRG and family try to stay below the radar in their new town, but a classmate of Claire's with some powers of his own knows there's something different about her. Matt Parkman and Mohinder Suresh are now guardians of Molly Parker, who has been suffering from horrible nightmares about the man who is more evil than Sylar. Mohinder and HRG are still trying to take the company down. Kaito Nakamura and Angela Petrelli receive ominous notices of their impending deaths, clearly sent by one of "the elders". Nathan has pushed his family away and is in a very dark place, feeling that Peter has survived and is alive somewhere. In Ireland, we find Peter Petrelli is alive, but doesn't remember who he is. Maya and Alejandro, two new characters, are wanted for murder due to her accidentally killing multiple people because of her ability to host a plague.

Hiro learns of his father's death and travels back in time to save him only to realize that he must let events unfold as fate intended. He does however recognize his father's killer. Matt Parkman realizes that he has the ability to implant thoughts in other people's minds. He wants to know the identity of the woman in the photo with his father. When Bob and Suresh kidnap Claire Bennet, HRG and West set out to rescue her but get their own bargaining chip beforehand.

In order to change the course of history, a scared and cynical Peter Petrelli travels back in time from four years to the day his brother Nathan revealed the existence of the super-humans and was the one who shot him. In attempting to capture future Peter, Matt Parkman gets teleported to a desolate African landscape. In Japan, Hiro takes control of his father's company when, courtesy of a DVD, he and Ando receive instructions from Hiro's late father about a deadly secret contained in the office safe. Hiro can't help but open the safe and the contents are promptly stolen by a "speedster"; a woman with super-fast speed called Daphne. Meanwhile, Nathan undergoes a religious experience while recovering from the shooting and is offered a new job in Congress by a shady blond government woman named Tracy Strauss, someone who looks remarkably like the late Niki Sanders. Elsewhere, Sylar confronts Claire, whose alone in her house, in a bid to get hold of her powers.

In Haiti, Peter and the Haitian try to rescue Nathan who has been captured by the sinister Baron Samdei and his militia army. At Pinehurst, Mohinder finds himself a captive by Arthur who wants his powers back for a grand master plan, in which Mohinder attempts to find Maya to ask for help since she may be powerless too. In Kansas, Matt Parkman learns the true nature of Daphne without her super speed, while Ando and an immature Hiro seek answers to their powerlessness in a comic book store in the late Isaac Mendez's '9th Wonders' series detailing their conflict as it happens. In California, the powerless Claire is taken to the hospital dying from her wounds, while Sylar and Elle turn from hunters to the hunted when the vengeful Mr. Bennet attempts to track them down to kill them.

Having traveled back in time 16 years, the immature Hiro seeks out his late mother to try to get his memories back, while Claire has a run-in with a younger Noah Bennett when he was assigned by the company to look after the infant Claire and how she may have become the catalyst for the secret formula. Back in the present, Nathan returns to Pinehurst where Tracy introduces him to a group of U.S. Marines that Arthur has recruited to be his army of super-solders once Mohinder gets the catalyst for the ability-giving formula correct and which hopes the formula will be able to cure his disease... and begin Mr. Petrelli's quest for world domination. Peter and the Hatian return to New York and are sent by Angela in desperate attempt to break into Pinehurst to kill Arthur Petrelli before he can complete the formula. Meanwhile, Ando, Parkman, and Daphne seek out a bicycle messenger who may have the last '9th Wonders' comic book works to learn more about the future and where Hiro is and what to do to save him. Elsewhere, Sylar goes rogue once again by disposing of Elle, and then decides to go after both the heroes and villains to steal their powers for himself.

Noah, Claire, Angela, and Meredith find themselves trapped at the Primatech by Sylar who locks them in the building and subjects them all to various mind games. Meanwhile, Matt, Daphne, and Ando seek refuge at the Mendez loft where Daphne plans to steal a sample of the power-giving formula to give to Ando who wants to rescue the powerless Hiro still trapped 16 years in the past, who continues to struggle to find his true origins with his younger self. Back in the present, Peter faces off against Nathan, Tracy and the security detail at Pinehurst to stop Mohinder from reproducing the formula, and finds allies in the form of Knox as well as Flint who also want to stop the production of the formula, leading to a fiery showdown for all.

Hiro's life hangs in the balance as his brain tumor worsens, prompting him to subconsciously deal with some of his past decisions. Meanwhile, Sylar pays Claire an unexpected visit to get answers as to why he isn't quite himself. Elsewhere, Samuel's plan to impress his long-lost love, Vanessa, takes a terrifying turn.