Shares of iconic theater chain AMC Entertainment (NYSE:AMC) are up a stunning 530% in the past month alone. Behind the momentum are the 10-million-strong traders/followers/influencers from the legendary WallStreetBets subreddit. There wasn't much news per se that led to yet another short squeeze in the hot turnaround stock. Perhaps investors started to realize that there is a massive backlog of films from blockbuster franchises that are all scheduled to hit the big screen within the next two years.