Felicity's mother Donna arrives in Starling City just as a terrorist group calling itself Brother Eye unleashes a wave of cyber-terror on the city. as Felicity struggles to find the villains, she realizes that they're using a computer virus that she created. Meanwhile, Oliver and Thea try to address their differences, and Laurel makes an error of judgment because of her guilt.moreless
In the season finale, Jack discovers the alarming depth and scope of the organization to which he's lost Amy. Meanwhile, Marcus and Madison engage in a fatal struggle; and Richard is forced to go on the run, but he recruits an unexpected partner along the way.moreless
Jack makes a last attempt to bring Amy home, after making a gruesome discovery in his backyard. Meanwhile, Rose remains haunted by a tragedy; and Gary realizes how to expose the corruption behind Qui Reverti but it will require a great sacrifice.moreless
Madison's instincts gain strength as she begins to make sense of Marcus' memories; Jack gets a terrifying confession out of Gary; Richard comes face-to-face with Marcus.
Gary learns something very strange about Amy, which suggests a larger, more terrifying conspiracy. Meanwhile, Madison arrives in Seattle and threatens an old acquaintance; Rose puts pressure on Richard; and Jack and Gary find a reliable source.moreless
Jack searches for Amy in Seattle, but her movements produce more questions than answers. Meanwhile, Madison finds herself in a train station with a ticket to Seattle, an envelope with money, and a mysterious key; and Richard suffers serious consequences due to an act of humanity.moreless
Members of a secret society chase immortality by seeking refuge in the bodies of others. In the opener, the wife of a retired cop vanishes on her way to Seattle on business. As her husband searches for her, he is asked by a friend to help with a murder case. Meanwhile, a 9-year-old girl starts behaving erratically after seeing a stranger on a beach; and an assassin desperately tries to stop his secret from becoming known.moreless
Kiera asks for Alec's help when a dangerous drug from the future makes its way onto the streets. Jason warns Kiera about freelancers from the future. Meanwhile, Travis and Sonya fight against each other.moreless
The fate of humanity is on the line as Walter plans to make the ultimate sacrifice to stop the Observers before they were ever created.
To penetrate the Observers' headquarters and rescue Michael, their only hope for victory, Olivia must use her abilities and meet with some old friends.
While Walter tries to learn more about the mysterious Donald after Michael's revelation, Windmark undertakes his own quest for knowledge.
The team joins forces with Nina to recover a key piece of the plan that Walter created to defeat the Observers.
While Olivia and a recently-recovered Peter investigate a mysterious signal coming from a forest, Walter uses LSD to try and recall his memories of his plan to defeat the Observers.
Peter reaps the consequences of spying on an Observer leader. Meanwhile Olivia's search for another tape leads her to a woman who seems to be able to divine the future.
The fight against the Observers intensifies and a Fringe team member plans an attack on his own.
The Fringe team investigates a pocket reality occupying an apartment building, and Peter learns that he has the power to stop the Observers.
Peter takes extreme measures when the team learns of a way to stop the Observers from changing Earth's atmosphere and wiping out humanity.
After infiltrating a subway station to recover a vital piece of Walter's plan, the Fringe team meet up with an old friend... and must determine if he can be trusted.
The Fringe team meets with a group of humans who have taken refuge in the forest and seek to preserve humanity's history any way they can.
After Walter's mind is damaged by Windmark's telepathic probe, the team goes to Walter's old Harvard lab to find the information they need to defeat the Observers.
In the year 2036, Peter, Astrid, Walter, and Etta set out to find Olivia and free her from amber. Once they do, they discover she holds the key to finding the plans for a weapon to defeat the Observers... but Walter is captured and interrogated for the same information.moreless
The Fringe team is pushed to the brink as they try to save every living person from the schemes of Jones' superior.
Walter is forced to relive his past while investigating a series of spontaneous human combustions, while David Robert Jones begins his end game.
The Fringe team on both sides fight a common cause and developments are made regarding the Cortexiphan children.
In the year 2036, a new Fringe team takes on the Observers in a war that will change everything. But to win, they must resurrect a legendary figure from their past, someone who holds the secret to defeating the Observers once and for all.moreless
While David Robert Jones goes after his next target, Walter visits the Other Side to help the team's counterparts with an investigation into a Fringe case that touches on both worlds.
Lincoln teams up with the Other Side and together they investigate a vigilante with a connection to the shapeshifters.
The team investigates a case involving a bizarre mutation that Peter solved in his original timeline four years ago.