Producer J.J. Abrams says he doesn't know if Fringe will be renewed for a third season.

But he does know this: the second season finale of this Fox drama will somehow top the incredible episode that concluded its first season (in which we learned of an alternate reality in which the Twin Towers still exist).

"I think the whole alternate-universe idea is at the core of what's going to be happening," Abrams said earlier this week. "Without giving anything away, I think that the ending of this second season is richer and better and deeper than what we did last year."

While Fringe is off the air until April 1, it will return on that date and air seven consecutive episodes. The first one back, Abrams says, is worth keeping an eye on.

"It's one of my favorite episodes that we've done," he said. "It is particularly retro and weird. It's a really cool episode."

Aren't they all? Review the Fringe storylines to date by visiting our section of episode guides.

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.