It seems that what we learned last week in “6B” about the heightened emotional state playing a very important part in the ability to safely travel through universes has, in fact, been the basis of Walter’s research from the very beginning.

He knew that by using a device to cross, such as he did to save Walternate’s Peter from dying of the same disease his own Peter did, created such havoc on the fabric separating the universes that it was unwise to attempt to do so again, even if it meant Peter couldn’t get home.

For some reason, it was lost on me, when we first learned about Walter saving Peter from the other side, that he had every intention of returning him.

I’m not saying that it wasn’t made perfectly clear to other people, but in my mind’s eye he had intended to keep Peter and to save his wife, Elizabeth, grief. I’m embarrassed to say I have no idea why this was my impression, because I couldn’t have been farther off base.

"Subject 13" was filled with familiar characters with unfamiliar faces.

The entire episode takes place in 1985, and we see concurrently the consequences of Peter’s kidnapping in both worlds. As an aside, I love the retro beginning they use when doing a flashback scenes. It really taps into what we (the world) thought would be coming in the future.

We had ideas of rounded corners, groovy colors – an interesting take woven in someone’s imagination. The only thing it represents these days what we expected of the future in the past.

Walter, before he asked William Bell to remove a part of his brain, was still a goofy, fun sort of fellow. He worked well with the children. But you could also see his scientific side, when he told Elizabeth that Peter was not her son and basically not to get too attached.

Easy for him to say when he walks off to work every day leaving her to deal with a grieving Peter, lost and unsure of this world into which he has been thrust, frightened and lacking trust of faces that look otherwise so familiar.

After Peter tries unsuccessfully to get back to his own world by plunging through an icy Reiden Lake, Elizabeth’s packs she and Peter up and they go to Florida, where Walter conducts his research. In her desire to give him something to do and get a breath of fresh air, Elizabeth takes Peter to the research facility and it is there that he sees Olivia. As Walter says, “The beguiling Olivia Dunham beguiles.” There is no doubt that Peter feels some sort of connection to Olivia, perhaps because he can sense in her the same doubts he himself is facing.

In 1985 the past of our future story begins. Walter devises a series of tests to determine just what type of heightened emotional response causes Olivia to flash through the universes. He is unable to determine the exact formula until Olivia comes to school with a black eye.

Knowing that Olivia has a fearsome home life, where she suffers abuse at the hands of her stepfather, and that she is close to another young boy at the school, Walter arranges for her to be trapped in a darkened room, and when the lights go on, she is faced with the image of her friend, beaten and bloodied on the schoolroom floor. She immediately flashes and is gone.

As the call to arms to find her begins, Peter finds her book of drawings and following the only picture in the book that looks happy, tracks her down. Karley Scott Collins plays young Olivia with such grace and maturity, that even the subtlest of looks can be felt right in your heart.

As Peter approaches, she tells him stay away as all of the flowers around her have died due to the heat of her flashing. He says he is not afraid, and they hold hands. She thinks of being cool and it begins to snow. When she admits it was she who created the snow, Karley plays the scene exactly as Anna Torv would have played it. There is no mistaking the woman she is to become. This IS young Olivia.

This is important, because in last year’s flashback episode, Peter wasn’t played by the same chap he is in this episode. And, I don’t recall anything special about him. But Karley Scott Collins has a genuine spark, the gift of acting. When Walter was subjecting her to the many tests of heightened emotional response, it was just her and a room, and never did I question what she was feeling.

I felt like I was watching a young Jodie Foster, and if we have another flashback episode and Karley is not the one to portray young Olivia, her presence will be sorely missed.

In spite of all of Peters doubts and fears, he does have some trust for his erstwhile parents, and talks Olivia into trusting Walter with the situation with her stepfather. When they get back to the school, her book of drawings in hand, she demands to see Dr. Walter. When she is told it isn’t possible, she runs into his office, tears streaming down her face, admitting she had seen the blimp she drew in her book when she flashed to the other universe, begging him to help her with her stepfather, to please step in to make things right. Walter is stunned into silence.

Until he walks into the door behind her. Olivia had flashed, and the person she just trusted with her darkest secret, the real person Peter wanted her to trust, Walternate.

For six months, Walternate and his Elizabeth had been grieving over the kidnapping of their son by a man who looked exactly like Walternate. A part of him blamed Elizabeth for not judging by his clothing, anything, that the person who held their son was not him. No theories made sense. Not until a little girl infused with so much pain appeared before him, handed him her book of drawings and shared her secret and disappeared again.

It was a chill inducing moment, to imagine Walternate, no doubt completely befuddled at what was happening before him, but hardly immune to the words and pain being delivered by our Olivia. She left before him the book of drawings, inside of which is one of her holding hands with Peter. He had found his son.

So much of this episode was gut wrenching and difficult to watch; both children in such states of distress, but finding one another in the end. We know they don’t remember this interaction, but it had to have left an impression never to be lost to either of them. I wonder, given what we learn in “Subject 13” if Walter (or William Bell) had anything to do with Olivia ending up in the FBI. Did Walternate pursue Fauxlivia in the hopes that she would somehow lead to his son? Knowing the way in which these entanglements unfolded leaves even more questions.

The executive producers have said that as the story unfolds, they themselves are taking steps they didn’t expect on their way to the finale. Certainly our reaction to the episodes are having an influence, and it’s wonderful to know how in tune they are not only with their characters and story, but also how they are received by the public.

What did you think of this week's Fringe? Discuss!

Carissa Pavlica is the managing editor and a staff writer and critic for TV Fanatic. She's a member of the Critic's Choice Association, enjoys mentoring writers, conversing with cats, and passionately discussing the nuances of television and film with anyone who will listen. Follow her on X and email her here at TV Fanatic.