Fans of Fox’s “Fringe” may be worried.  Not just about the ratings and whether the series will make it to a fourth season. But about the fate of various characters and how they may all react when the truth is revealed that Olivia’s alternate switched places with her.

Actor Joshua Jackson say he’s worried about the impact that could have on his character of Peter.

“The last interaction he had with Olivia was, ‘I’m not quite sure how I feel about you, but I’m gonna take a huge emotional gamble on what we could be,'” Jackson tells TV Guide. “Now the payoff for that gamble was that he actually did fall in love, just not with the woman he was signing on for. How do you broach that conversation?”

But he won’t be the only character having a conflict as the season plays out. Jackson says that Peter will have some explaining to do when our Olivia makes it back in the next several episodes and that his relationship with alt-Olivia will have an impact on the duo.

“He gets hoodwinked at a time when you’d think he’d be a little bit more eyes-wide-open,” says Jackson. “And because he doesn’t figure [Bolivia] out and has no real hand in getting our Olivia home, I worry about Peter’s future. I think it may break the character. It’s like, ‘Who is this guy who keeps getting fooled?'”

Jackson isn’t the only one who sees interesting changes ahead for the central character relationships on the show.

“When our Olivia comes back, you’ll see how we all change suddenly, how the relationships will change. We have got to reestablish the game rules for the team,” says John Noble. “It will be really interesting to see how the Peter-Olivia situation is handled.”

Olivia will work on finding her way back to our universe as the next few episodes unfold. And to get back, she’ll get an unexpected ally in the alternative universe–Broyles.

Lance Riddick and Olivia Torv also tease that the alt-Rididck will be instrumental in helping our Olivia find her way back home.

“I figure out that she knows who she really is,” reveals Lance Reddick, adding that his by-the-book Fringe Division leader ultimately opts to betray his country after uncovering Walternate’s wicked plan to get his hands on the Cortexiphan in Olivia’s system. “He decides to save Olivia because they’re about to dissect her. She is the only one they have ever found who can cross back and forth between universes safely without any of the effects, and they want to know why.”

Back in this world, things are looking just as grim for Bolivia. With her cover blown and unable to secure an extraction back to the alternate universe, the Mata Hari winds up in federal custody and facing trial. But then something sick and certifiably Fringe occurs to send our home team into a tizzy. “Shock, horror, all of that,” is all Reddick will reveal of the twist.