Walter uses an LSD experience to jog his memory about a plan to beat the Observers. Meanwhile, Peter and Olivia follow a strange signal into the forest, but the trail leads to a shocking scene.
As their battle with the Observers rages on, the Fringe team find themselves in a forest populated by a group of people dedicated to recording the history of mankind.
Members of the Fringe team go to Walter’s former lab at Harvard looking for crucial information that could aid their current rebellion against the Observer overlords.
In the Season 5 premiere, Peter and Etta search for Olivia in 2036 as the Fringe team, released from amber after 20 years, joins the rebellion to halt the Observers’ world dominance.