Fans are eagerly anticipating the season finale of "Fringe" on Thursday night (May 20). With a rift in the Bishop clan, the entire crew trying to save the world from an alternate dimension and the possibility that Peter is the key to the end of the world, anything could happen.

John Noble and Joshua Jackson, who play the Bishop father/son combo, said the show's final few minutes will really leave fans shocked.

"You have to watch the last five minutes ... and that will tell you a lot," Jackson revealed earlier this week to MTV News.

Noble said that even he isn't sure if Peter (Jackson) is the key to saving or destroying the universes. "It's only Walter surmising that that's the case, so science, as we know it now, would suggest that unless we do something rapidly, it could happen," he said. "But it won't happen, because we have a story to tell, and being very inventive people, we will find a way to get past that problem.

"The interesting thing about 'Fringe' is, the only character that doesn't change is Peter," he continued. "Peter is the constant, and this season we've been talking about Peter a lot. ... It's all been building. When Walter said in the last episode [that Peter] could be responsible for the end of the world, it's actually about Peter. So we have this tug-of-war between two universes for this character, and I play both dads."

Fans, however, wonder when the rift between the Bishop men will eventually mend. "Isn't that the foundation of a good story? Isn't the whole point that they never get to the end of the story until the show is off the air? But that's what family is too," Jackson said. "We were making progress. We become closer together. Circumstances, like being from an alternate universe, come and tear you apart and then slowly repair."

What do you think will happen on the "Fringe" season finale? Share your theories in the comments!