Timn Kring told SciFi Wire that there will be a season-long arc involving the hunt for a serial killer with super powers.

"We are bringing in other people with super powers, and they are not necessarily heroes," Kring said. "The show does introduce the concept of a major villain in the second episode, and that villain becomes a sort of a linchpin, a central character for most of the first season."

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"He's recruited by this FBI agent, the character that Clea plays," Grunberg said. "They become this team, sort of like a Mulder and Scully of 'The X-Files.' And what's great is that this side of the story -- investigating the villain and trying to figure out who he is, what his motives are, why these people are being affected and what's going on -- what's great is, the audience will have a lot of these questions, and my character is going to discover them and hopefully answer those questions and be the eyes of the audience."

The heroes of "Heroes" may not remain good guys, Grunberg warned.

"Don't assume that every one of these characters is good," Grunberg said. "That's something so interesting. As actors, co-star Masi Oka and I have had this conversation where we're thinking, 'Are we going to be good? Are we going to realize, "Wow, these powers: They're empowering me to such a way that I can use it for evil purposes?' I mean, we have no idea whether we're going to go good, go bad. It's just so interesting to see what somebody would do given these abilities."
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Source: SyFy Portal