We're all really pumped for Portal 2, which means we will take any excuse to watch the trailer over. Over and over and over. Like a monkey with a miniature cymbal. So here is a Frame By Frame a.k.a. our excuse to be complete nerds over the little slivers of game knowledge these developers feed us.

Developers love to sneak things by us, and the best possible way to do so is in trailers. Even in small teasers there can be countless hints towards possible gameplay mechanics, story reveals, and other subtleties. Often, to find them all, you need to go frame by frame, looking everywhere for everything. It's a bit of a pain, so we decided to take that strain off of you. That's the concept behind Frame by Frame.

Written by: Jon Cooper, Sarah LeBoeuf
Edited by: Paul Ritchey