Hollywood studios don't want to make a superhero movie. They want to make three superhero movies. Or five. While it's great to have a hit movie, it's much better to have a franchise -- a series of films that can keep generating money for years. This summer is packed with superhero movies that are looking to launch new franchises, like "Thor," "Green Lantern" and "Captain America." And this weekend, "X-Men: First Class" will restart its series with a prequel that shows how the mutant team came together in the 1960s. So which superhero franchise has made the most money overall? We added up the domestic grosses for all the major comic-book movies and determined which hero made the most at the box office. Click ahead to see which series came out on top. Watch clips from 'X-Men: First Class' >>