Walter explains to Olivia how Peter came from the alternate universe, and how he was willing to risk everything to save his son.

The alternate universe Fringe Division investigates a shocking breach of security when a twin frees his brother from a quarantined Amber area. As the team sets out to crack this sophisticated case, Walternate experiments over there more with Olivia as she reenters the tank. Meanwhile, visions of Peter continue to haunt Olivia about returning to the “other side”.

Peter, Olivia and Walter come face to face with a mysterious and terrifying Fringe event as they get trapped in a town that there’s no escaping from.

When the Fringe team tracks a lead into a hostile and heavily guarded location, Phillip Broyles resurfaces…but can he be trusted?