Season synopsis
Contains spoilers for this season and earlier seasons.
FBI agent Olivia Dunham is drawn into the Pattern, a string of bizarre events tied to experiments at the edge of science. After a biological attack leaves her partner John Scott dying, Olivia persuades institutionalised scientist Walter Bishop to help, with Walter’s estranged son Peter brought in to secure his release and interpret his work. Olivia, Peter and Walter investigate cases with the new Fringe Division, while Astrid Farnsworth assists Walter in the lab and Phillip Broyles oversees the team.
The cases expose links to Walter’s former research partner William Bell, the powerful company Massive Dynamic, and a covert organisation known as ZFT. David Robert Jones, a former Massive Dynamic scientist, escapes custody and pursues technology capable of opening a passage between worlds. Olivia also learns that Walter used Cortexiphan experiments on children, including her, to develop unusual abilities. Walter’s fractured memory and guarded relationship with Peter point to a history he has not explained, while the recurring Observer appears at major events without revealing his purpose.
After Jones attacks Nina Sharp and steals an energy cell hidden in her prosthetic arm, he uses it to open doorways between worlds, but his attempts at the wrong coordinates fail. Walter disappears with the Observer, who brings him to the Bishops’ beach house to recover a device that can seal a crossing. Olivia, Peter and Walter intercept Jones at Reiden Lake as he opens another window. Peter triggers Walter’s device, sealing the doorway and killing Jones. Nina tells Olivia she can arrange a meeting with Bell. Olivia travels to Manhattan, where an elevator transports her to the parallel universe and Bell’s office inside the still-standing World Trade Center.