WHAT IF... Vol. 1, Issue 9
Marvel Comics has had success in the past with a comic title known as What If... (one series from 1977-1984, the other from '89-'98--they now publish each one as a one-shot instead of as an ongoing series), which is a title they created that shows what would have happened to certain storylines in their comics had the story taken a different path (for example: "What If Spider-Man Joined the Fantastic Four?", "What If the Hulk Had the Brain of Bruce Banner?"). On the whole, the formula used in this show is similar to the ones used in this episode.
A specific issue sticks out in my mind, however. Usually, the What If... comics are hosted by the Watcher--a cosmic being who can see into alternate realities. However, one issue--What If... Vol. 1, Issue 9 (or "What If the Avengers Had Fought Evil During the 1950's?")--is told in a different way. Iron Man calls four of the other Avengers (Captain America, Thor, the Vision, and Beast, for those of you who are interested) into a meeting only to reveal a machine he has created which can show them alternate realities--namely, that reality which answers the question What if the Avengers had been formed during the 1950's. All five of the Avengers go on to watch on a view-screen what would have happened.