Rowan Longworth

Peter, Olivia, Walter, Astrid and Broyles face off against the Observers in one final and extraordinary battle for the fate of mankind.

Walter follows leads to a key piece needed to defeat the Observers, while a member of the Fringe team takes on a new role.

In an attempt to recall his plan to defeat the Observers, Walter takes an LSD trip down memory lane in search of answers. Meanwhile, Peter and Olivia trace a mysterious signal into the woods, where they come upon a grisly scene.

As Peter, Olivia, Astrid and Walter scramble to tap into a key piece of the puzzle to defeat the Observers, they enlist the aid of Nina Sharp who conjures up a plan.

The thrilling worlds of Fringe near the end in the first part of a two-hour series finale as Olivia embarks on a dangerous and otherworldly journey into the unknown.

As time dramatically ticks down, Peter, Olivia and Walter stop at nothing to save the universe from Observer rule. Walter enters the infamous deprivation tank in an attempt to uncover a key piece of information about the mysterious figure, Donald. Meanwhile, Captain Windmark sets out on a revealing mission of his own as long-standing questions are answered.