A sad heaviness permeates this week’s episode of ‘Fringe.’ Everyone is tense and weary. Olivia’s hair is pulled back tight in a braid, and her words are sharp, her body wound tight. Walter lumbers around his lab hunched over as though he carries a burden on his shoulders. Even the sunlight seems somber. This world is quiet and hollow. This is the world without Peter Bishop.

This week Olivia and Lincoln investigate the deaths of two 12-year-old boys; they died in a tunnel from unusual means. At first, Walter thinks that the boys died from an invasive new species of fungi that uses hosts to spread its spores. Olivia and Lincoln find the boy, Aaron, who was there when the two boys died.

Aaron is taken to the lab so Walter can examine him. Because Aaron has nowhere to go (dad’s dead and mom’s out of town), Walter lets him hang out in the lab. When Olivia tries to destroy the fungus by burning it, Aaron’s temperature rises. Walter figures out that the boy and the organism are connected. According to Walter, what is in the tunnel is a self-aware fungus that has formed a psychic bond with Aaron. The fungus will react to Aaron’s emotions. Their bond developed during Aaron’s trips to the tunnel; he felt alone, but when he was in the tunnel he felt a presence that shared his loneliness, and together they no longer felt alone. The organism, which uses hosts to grow its neural network, spreads too far, threatening innocent people. Broyles wants the fungus destroyed immediately, but Walter wants to save Aaron. Walter convinces Aaron to let go of his friend. Once Aaron severs his bond with the organism, the fungicide kills the huge fungal mass.

‘Alone in the World’ reminds me of the second season episodes ‘Brown Betty.’ During ‘Brown Betty,’ Walter watches Ella, Olivia’s niece, for the day. He entertains her with a story. Both episodes show Walter as the man, the father, he could be when not obsessed with work and power. This Walter bonds easily with children by treating them with respect, talking to them, and being a bit funny. In this episode, the best scenes are with Walter and Aaron. Walter gets Aaron to open up; Walter makes tin foil hats and milkshakes. He tells the boy about Peter: his Peter was sick and before Walter could cure him Peter died; he discovered the other universe, crossed over, but when he came back, the ice broke and the other Peter drowned. Walter watched Peter die twice. In this timeline, the Observer did not help Walter save Peter. At first, Walter sees Aaron as Peter, but by the end, Walter sees Aaron as Aaron and is determined to save him. The scenes between Walter and Aaron are genuine. These moments could have taken a sappy turn, but the acting skills of John Noble prevent that from happening.

The best part of the episode occurs during the last five minutes. For three weeks, Walter has been seeing the reflection of a strange man and hearing his voice; this is Peter trying to contact Walter. Frustrated, confused, and determined not to be sent back to the mental institution, Walter tries to lobotomize himself. This event is believable. During the past three episodes, John Noble has portrayed Walter as a Humpty Dumpty type man—he’s been broken, shattered, and now the tape that has been holding him together all this time has started to unravel. The way Walter talks, walks and reacts to situations now is completely different than last season. All the progress Walter has made has been erased. And it’s been heartbreaking, yet mesmerizing, to watch.

Olivia enters the lab. She calls for Walter. He does not respond. She finds him in his room. Walter has just started the procedure. She takes the hammer and spike from him. Fortunately, Walter is not severely injured. Olivia convinces Walter to tell her why he would do such an act on himself. He reveals the truth about seeing and hearing Peter. Olivia takes out a piece of paper, unfolds it, and shows Walter a drawing of Peter. She’s been dreaming about Peter for three weeks. Walter’s face changes; his eyes brightened, and we see a hint of the old Walter. If she has seen the man, then he must be real. Walter tells Olivia that they have to identify and find this man.

The teaser for next week shows Peter returning from wherever he’s been. Since both Peters died, I wonder—how many Peters will come back? With new timelines for both universes in place, the writers have room to play. It is completely plausible for two Peters to return. Imagine the alt-Peter. He would’ve been raised by Walternate, but Walternate only became cruel because his son was taken from him. With Peter in his life, Walternate would be a completely different person. Of course, this is if Peter’s return alters the timeline.

What if Peter returns and no one remembers him? It would be as though he was in suspension for a short time, the world changed, and he reenters the world without knowing about the changes. It would be as though you were locked in a closet and when you came out all the rooms in your house were different, and the people you lived with acted as though everything was normal, nothing had changed, and forgot you even existed. I’m very intrigued by the possibilities presented in next week’s episode. With Peter back, the show should get a jolt, creating the momentum essential for the rest of the season.

If you missed last week’s episode be sure to read my ‘Fringe: One Night In October’ Episode 402′ recap to catch up.