Greg Grunberg, Heroes

As Heroes enters its final three episodes of the season (Mondays at 9 pm/ET, NBC), the lines are (literally) being drawn for a multi-hero crossing of paths at the mysterious Coyote Sands. But will this creepy burial ground become the new Kirby Plaza?

"Everybody does come together at Coyote Sands," Greg Grunberg tells TVGuide.com. But after last week's reunion with the son he never knew he had, Grunberg's Matt Parkman will have a whole new set of priorities in the remaining episodes and beyond.

"The baby and his family is the reason Parkman is going to do something in the last episode that he may regret for the rest of his life," Grunberg says. "It's a huge story that we play out — something that only a guy who's been pushed and is desperate to save his family would ever do."

So how does the recently resurfaced Janice — Parkman's cheating ex-wife who disappeared early in Season 2 — figure into this family unit? "We've got a lot of stuff to do," Grunberg says. "It's definitely a strained relationship. It's going to take some time and some real emotional scenes for them to get back together. But I think that's what people are going to want to see. I think when Janice finds out that Matt's been thinking about her and just wanting this relationship so bad, that it's going to work."

But Grunberg suggests getting through their past issues won't happen overnight. The actor revealed that Janice has even more secrets than viewers may have guessed, especially relating to the "touch and go" powers of the couple's baby.

"It's going to take some work," Grunberg says. "How much can you trust a person who was dishonest with you? She's got secrets of her own — Janice is not as simple a character as everybody thinks. Where did those diamonds go [in Season 1]? There's a lot of things we don't know. We made a baby with powers together, and I don't think that's a one-sided thing."