Did you catch the X-Files reference? I know you're wondering why I'm bringing this up first, and I'm not sure if I've mentioned this before, but The X-Files is my favorite TV show of all time. If you didn't catch the reference and have it recorded, got back to 2:33. The victim of the shapeshifter is watching an episode of The X-Files. The episode in question is Dreamland Part II. If anyone remembers the episodes, it involves Mulder switching bodies with an Area 51 employee. I'm not sure if that counts as foreshadowing since most people either missed it or couldn't recognize what it was, but it certainly related to the episode. There was another reference with Broyle's saying something about X designation whatever that means.
Just a warning, I'm not the biggest J.J. Abrams fan except for his work early in Alias (maybe Felicity). I won't go on ranting and raving on how great he is; I think he goes for thrills and twists as a priority instead of the story. That's a perfectly reasonable way to make shows, and people like it.
I loved the discussion in the supermarket between Walter and Peter. Apparently Walter thinks Peter liked custard as a child and Peter insists he didn't. This kind of innuendo about the alternate universe is part of Abrams that I love. Walter seems to be trying to make it up to Peter like somehow some custard is going to repair any damage ripping someone out of another universe causes. The scene in the end where Astrid, Walter, and the cow said happy birthday to Peter was very unsettling.
Most of the episode, Olivia was bedridden after get thrown through a car window from the alternate universe. How she got from the WTC to the car is anyone's guess. She doesn't remember any specifics, but know there is something urgent to do. I think too much of the episode was spent on Olivia since we knew she wasn't going to die, but her condition does seem to push Peter and Broyles to action.
The shapeshifter thought it had killed Olivia, but when it failed, whoever was only the other side of an awesome typewriter ordered it to interrogate her, and then eliminate her. It fails after quick thinking by Peter and is cornered underground. Charlie supposedly kills it, but the last scene reveals that it had in fact killed Charlie and has taken his place. Predictable? Yes. Cool? Yes. I guess we now know what Kirk Acevedo meant when he got fired. He'll probably be gone by midseason. There's no way an imposter can last for a whole season. Oh wait, Lost season 5...
Charlie's new replacement is Agent Jessup who was exceedingly boring and annoying until we see her connecting Pattern events with Biblical phrases. She seems like a very generic character, but her belief that somehow the Pattern is related to the Bible is certainly interesting. That does not make her character interesting though, but then again, I don't find any character in the show interesting other than Walter.