I Wish I Hadn't Known - Lost: Through the Looking Glass
I'm still kicking myself that I had read the spoiler about the Lost finale, because I would have loved to experience that WTF? moment at the end. It would have ranked up there with those moments in The Sixth Sense or The Crying Game. Lucky you if you weren't spoiled.
They did a pretty good fakeout job, making it seem like it was a flashback to the past. The ambiguous clues:
1. Sun and Jin lookalikes were sitting behind Jack in the opening flight scene, and they didn't know Jack. Could be one of those random crossovers in flashbacks.
2. The Razr phone was actually out in 2004. Dr. Jack could be enough of a techno-geek to get one when it first came out.
3. Sarah's pregnancy. It could have been after the Hunting Party and the Thailand trip, but before he left for Australia.
4. Dr. Hammill saying "You're a hero twice over." Then he goes on to say how Jack pulled the boy from the burning car, and went back again to save the mother.
5. Christian alive?: Jack had a prescription from him and he told Dr. Hammill to call his father down and see if he's more drunk than him. That places it in the past for the viewer. But at that point Jack was pretty messed up so Dr. Hammill could have dismissed it as drunken ravings. The prescription is easy -- it's written on Christian's scrip stationery, which would be easy for Jack to obtain after island too. (The Jack expert would have realized there would not be a new chief of surgery at St. Sebastian's until after All the Best Cowboys, upon which we are led to believe Christian lost his medical license altogether. But this setup was probably good enough to dupe the regular viewer for awhile.)
6. And of course: Not showing who Jack was trying to phone till the very end. Kate emerging from the shadows was the real payoff to the time-switch.
The only stronger clue before that were the maps of the Pacific spread out in Jack's apartment. He's becoming like Locke in the flashforward *shudder*, obsessed with the island and its power. Saying "we weren't supposed to leave." You could just hear Locke saying "This wasn't supposed to happen."
What hit me hardest about Jack's despondency how he flies back and forth across the Pacific, hoping the plane would crash so he could get back to the island. He's truly lost in this flashforward, and my heart breaks. And is Kate there for him when he needs her the most? Unh-unh. She got her deal, she got a new life, and she's moving on. This is the future that shouldn't be. Whether they go on in more flashforwards here, or have Jack finally make that next plane crash to bring him back to the island, the course correction will be a big part of Season 4, I think.