Sacrifices will be made and both universes may never be the same again after Walter and Olivia visit the “other side”

Olivia travels to the parallel universe with Walter, who faces-off with William Bell

Peter teams up with Sheriff Mathis on a mysterious murder case; Walter faces the possibility of being sent back to St. Claire's; someone from the ``other side'' visits.

Walter deals with upsetting news and tells Olivia's niece a fairy tale.that includes musical performances by Olivia and Agent Broyles.

A shape-shifting embryo is discovered; Peter shares a family secret with Olivia.

While investigating the mysterious deaths of passengers on a commuter train, Peter remains suspicious of Walter; the investigation leads the team to a a very powerful man (Peter Weller).

A perfectly healthy woman inexplicably dies; Olivia tries to keep Walter's secret from Peter.

Walter flashes back to 1985 while explaining Peter's otherworldly origins to Olivia. Also, Peter's mother is introduced, and details of the neighboring world reaffirms that there is more than one of everything.

When the sole survivor of a building demolished by an earthquake in downtown Manhattan proves to be from the other Earth, Walter leads the team to Jacksonville, the source of a related experiment that he and William conducted years ago. Now only Olivia and the secrets of her past can prevent another catastrophe.

Unseen killers target a wedding with a toxin that targets specific individuals, and Walter discovers that the case may be tied to a branch on the Bishop family tree.

While investigating a case in an office building where a man's blood literally burst from his arteries and veins, Peter and Olivia are trapped in a CDC quarantine when it's discovered that the blood carries a deadly pathogen.

The Fringe team travels to the town of Edina to investigate a cover-up and are greeted with hostility by the locals. They discover that many of the residents are disfigured, but have managed to hide their deformity... and will to go to any lengths to ensure their secret.

The Fringe team travels to the town of Edina to investigate a cover-up and are greeted with hostility by the locals. They discover that many of the residents are disfigured, but have managed to hide their deformity... and will to go to any lengths to ensure their secret.

A teenage girl awakens after an incident leaves her brain-dead... but she now starts reciting submarine launch codes in Russian.

The Fringe team investigate a mental institution after a patient has brain surgery and begins to show an improvement despite having his brain exposed. Agent Dunham makes a discovery of her own after seeing footage from the surveillance tapes.

The Fringe team investigate bodies with creatures attached to it. Olivia, Peter and Broyles discover that the case is linked to a dangerous organization.

The Fringe team closes in on the mysterious Observer after they investigate a bizarre abduction case in Boston, MA.

The Fringe Division investigates an unusual kidnapping with connections to Massive Dynamic.

The Fringe team investigates instances of victims being transformed to ash by high-energy discharges, and discover a connection to Broyles' past.

A man attacks his boss after a disturbing dream and the team travels to Seattle to investigate. Meanwhile, Broyles needs to meet with Nina Sharp.

Agent Dunham, still recovering from her traumatic visit to the alternate reality, is given a concoction by Walter to help her remember. Another woman being experimented on by Walter is introduced. Meanwhile the Fringe team look into a series of robberies that are linked to shapeshifting.

Peter, Olivia, and Walter race against time to investigate the bombing of a train station. Walter discovers something unusual about the human remains.

The Fringe team travels to Pennsylvania to investigate an underground tunnel full of human remains. Meanwhile, Walter experiments using frogs to travel between realities.

Season two opens with Olivia's shocking return to this perplexing alternate reality, while Peter is unknowingly in a race against time with an ominous mobile force pursuing information about Olivia's visit. Walter reenters the lab to cook up some fringe s