A child glows and smiles and breathes softly into the heart of a dandelion, sending sweet seeds into the breeze of a silent summer day. Peter and Olivia turn to each other and smile, then beckon to their daughter with hands held wide open only to receive flashes of whited out memory, emptiness and despair. The aliens known only as the Observers have arrived, precise in their pressed suits, determined hats and clean heads. With bright, cold efficiency they burn buildings, cruelly, calmly, acquiring what is not theirs. They advance on the girl but is she truly taken? Peter and Olivia are left with only the fragmented memory of a decimated day. Peter wakes abruptly, gasping for clear air. It is 2036 and he is recently released from the amber that held him in stasis for over 20 years. He found his daughter Etta and is secreted away with Walter and Astrid. Yes, Etta is alive, a young adult, posing as a member of the Observer sanctioned police force but loyal to the struggling, ragged resistance. The Observers occupy the city, poisoning the people, systematically erasing hope. Olivia is missing but Peter refuses to abandon faith and is determined to find her. It is interesting that Peter, who began this series as perhaps the most cynical part of the crew, has progressed to the point where he is the fierce defender of promise and belief in things working out. Walter explains that one of the Observers, September, turned against his own people and helped Walter devise a plan to defeat them. He placed the fragmented parts of the plan, separate and protected from each other, in Walters brain to keep them hidden from the other Observers. When it is time to implement the plan, Walter must retrieve certain components in order to reconstruct it. Olivia was searching for one of those missing pieces - a Thought Unifier - when she disappeared 21 years ago. Walter is a fragmented figure throughout the many incarnations of Fringe. Though every season is more or less a reboot Walter is never whole in any aspect. While he has recovered the missing parts of his brain as seen in the previous season, still he is partitioned, this time by September. He is forever searching for the missing pieces of himself, and we are never sure if the whole will be greater or crueler than the sum of its parts.
The team descends upon Columbus Circle in New York City where Olivia was last heard from. The Observers defiled Central Park, paving over its glorious green space to build horrific machines to pump carbon-dioxide into the atmosphere. The earth is too oxygen-rich for them. This process will shorten the average life span of a human being to 45 years. The building across the street is encased in amber but holes have been sliced out of it. The people, still entombed in their amber coffins, were removed by scavengers and sold on the black market. Olivia was one of them but the Fringe team track her down. They save her but in the process they lose Walter who is captured by the Observers. Olivia is released from the amber and meets her long lost daughter in a fragile and moving reunion. She still has the Thought Unifying device that Walter needs to reassemble the displaced parts of the plan. Walter is bound to a chair and interrogated by an Observer. He desperately dreams of music trying to build a wall in his mind to ward off the Observers telepathic intrusion. Music is alien to an Observer - it reeks of jarring tones and empty vibrations. To Walter it rings of hope. In this place of utter debasement and despair, there is beauty, even if only within his own head. The Observers are corporate consciousness embodied. They are clinical, economical, disinterested in anything or anyone unless it leads them to what they desire at a given time. Their cruelty is calculated and casual. They are themselves fragments, unable to connect to a larger universe outside of their own hedonism. Etta, Olivia and Peter visit a resistance stronghold. The techies there have devised a way to make someone appear dead when they are not. Working together, they use this knowledge to contrive a scheme to enter Walters prison and free him. Before they leave, Peter and Olivia share a searing moment away from the others, revealing their ragged souls in a shattering scene of anguish and longing. The loss of Etta splintered their hearts into brittle pieces, they turned away from love and are now painstakingly eking out a way back to each other. Walter writhes in agony as the Observer invades his brain searching for the plan to defeat them. After discovering the partitioned thoughts, the Observer brutally begins to extract them from Walters fracturing mind. Walter cannot help but form an image of Etta as a child in his consciousness and the Observer determines that she is somehow helping him protect the plan from the Observers assault. Walter continues to fight but he is breaking blood streaming from his nose and mouth, vessels ripping and tearing within his haunted eyes.
The Fringe team breaks into Walters prison using the apparently dead Peter as a way to gain access. The soldiers believe Etta is simply returning captured resistance fighters and let her inside. The place is curiously like an old seventies office building with dilapidated paneling and drones typing away between flimsy walls behind feeble doors with filthy, frosted glass. Making their way through the corridors of this tragic, damaged space they find and disable the machine the Observers use to seed the air with carbon dioxide. When an alarm sounds Walter is left alone and Etta and Peter rescue him. Fighting their way through the halls the team escapes in their battered van but Walter is in bad shape. Astrid gently wipes the blood seeping from Walters ravaged face. Clinging to her hand, Walter asks Afro (Astrid) if she has any music. With the team reunited, Walter is given the Thought Unifier device in order to ascertain the plan September placed in his brain so many years ago. But it is useless. The Observer has ripped his psyche apart with such savageness that Walter cannot even remember there was a plan. Astrid shows Walter the hand of William Bell, Walters one-time colleague, encased in amber and implores him to remember why he asked her to bring it. He cannot. The hand is needed to access a storage facility but this means nothing to Walter in his present state. Etta believes the parts of the plan deposited in Walters brain were destroyed while he was fighting the Observer and he will never heal. The plan is gone. Walter wakes from troubled sleep. Detecting gleaming flashes of iridescent light against the unforgiving brick wall of his room, he stumbles outside in his shorts and t-shirt and tattered robe to investigate. A desolate figure, shoulders hunched in anguish and despair, he makes his way to a mobile someone has fashioned out of old compact discs. Pulling a CD at random from a tattered bag lying on the fractured ground he slips it into an ancient player found in an abandoned car. Miraculously, Yazoos Only You peals out loud and strong. Gazing out the window he spies among the broken pavement and crumbling debris of a shattered civilization, a hint of persistent life a single flower shimmers like a quivering lantern in a wasted land.