Joshua Jackson Joshua Jackson

It's the moment Fringe fans have been waiting for since Peter was transported to the alternate timeline: a Walternate and Peter showdown.

Stranded in a reality where Walter (John Noble) rejects him, Olivia (Anna Torv) has feelings for another man and no one truly believes he's a Bishop, Peter (Joshua Jackson) will turn to the only other man who knows how the machine works, which Peter believes may be the key to returning to his own timeline.

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"It's sort of a Hail Mary pass on Peter's part," Jackson says of seeking Walternate's help. "He has a real, deep sense that he's in the wrong place and he needs to get home by any means necessary. Walternate is the very last person that he would ever go to, so it shows the level of desperation that he has to try and ask that man to help him."Turning to the man who could possibly be sending a new form of deadly shapeshifters to our universe is not the only complication Peter will endure in crossing to the alternate universe, especially considering this timeline's Elizabeth Bishop (Orla Brady

), Peter's mother, is still alive. "When he sees his mother, there's so much that is wrapped up in that relationship with his mom and the guilt over the loss of his original mom," he says.

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Whether the machine will simply transport Peter back to his timeline, or erase this new one altogether remains to be seen, but Jackson isn't as eager as some fans may be to get back to the original reality."We've spent many, many, many, many episodes with this group of people so I'm not sure that it's satisfying to just leave them," he says. "If we just pulled the rip cord on this new group of people and went to our old people, a significant amount of the audience would be like, 'Well, why did I get so invested in these people?' I don't know how they're going to resolve it and we haven't got to that place in the story yet, but that seems, to me, like that's going to be the crisis of the season."Fringe returns Friday at 9/8c on Fox.