Walter's nemesis Newton (Walter actually has more than one) is bringing people over from the other side to this, our, universe. The bodies from our side that this process engenders attracts the attention of Olivia and the team. There's a daring scene near the end, in which a bridge from the alternate universe is close to merging with a bridge from ours - over the River Charles in Cambridge, MA - with a view on the part of Newton of getting more people from there to here. Peter rushes to stop this - he doesn't want Walter to risk his life, and any contact with the other side under these circumstances would destroy anyone from this side. Only Walter or Peter have the scientific knowledge to stop the merging.
A nearby cop on our side gets exposed to the other side, and dies. Peter, who is also exposed, survives. Peter puts two and infinity together, and realizes the reason he didn't die is that he's from the other side.
Peter confronts Walter, who comes to see Peter as he's recuperating. The next we know, Peter's gone from the hospital. He's at large, furious at his father. Walter tries but doesn't quite explain to Peter that he had to take Peter from the other side, otherwise Peter would have died there. But whatever Walter is able to tell Peter, Walter has no explanation for why Walter didn't return Peter, after he had been cured. Not having the heart to break his wife's heart is not likely to be all that persuasive to Peter, given that his absence from the other world must have broken his mother's and his father's alternate reality hearts.
Will be very interesting to see if Peter is able to see his real parents - Waltnerate and his wife. I suspect that, in the end, Peter will still love our Walter, and will help him. But that could take a lot of time, and in the meantime, this great, defining season continues.
See also Top Notch Return of Fringe Second Season ... Fringe 2.2 and The Mole People ... Fringe 2.3 and the Human Body as Bomb ... Fringe 2.4 Unfolds and Takes Wing ... Fringe 2.5: Peter in Alternate Reality and Wi-Fi for the Mind ... A Different Stripe of Fringe in 2.6 ... The Kid Who Changed Minds in Fringe 2.7 ... Fringe 2.8: The Eternal Bald Observers ... Fringe 2.9: Walter's Journey ... Fringe 2.10: Walter's Brain, Harry Potter, and Flowers for Algernon ... New Fringe on Monday Night: In Alternate Universe? ... Fringe 2.12: Classic Science Fiction Chiante ... Fringe 2.13: "I Can't Let Peter Die Again" ... Fringe 2.14: Walter's Health, Books, and Father ... Fringe 2.15: I'll Take 'Manhatan' ... Fringe 2.16: Peter's Story ... Fringe 2.17: Will Olivia Tell Peter? ... Fringe 2.18: Strangeness of a Train
See also reviews of Season One Fringe Begins ... Fringe 2 and 3: The Anthology Tightrope ... 4: The Eternal Bald Observer ... 7: A Bullet Can Scramble a Dead Brain's Transmission ... 8. Heroic Walter and Apple Through Steel ... 9. Razor-Tipped Butterflies of the Mind ... 10. Shattered Pieces Come Together Through Space and Times ... 11. A Traitor, a Crimimal, and a Lunatic ... 12, 13, 14: Fringe and Teleportation ... 15: Fringe is Back with Feral Child, Pheromones, and Bald Men ... 17. Fringe in New York, with Oliva as Her Suspect ... 18. Heroes and Villains across Fringe ... Stephen King, Arthur C. Clarke, and Star Trek in Penultimate Fringe ... Fringe Alternate Reality Finale: Science Fiction At Its Best
Special Discount Coupons for Angie's List, Avis, Budget Car, eHarmony, eMusic
The Plot to Save Socrates
"a Da Vinci-esque thriller" - New York Daily News
"Sierra Waters is sexy as hell" - curled up with a good book