7. Hulk Meets Up With The Guardians Of The Galaxy - Avengers: Age Of Ultron
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The Theory: At the end of Avengers: Age Of Ultron, The Hulk (Mark Ruffalo) will fly off into space on a one-way mission in order to rid the world of Ultron's presence once and for all, bringing him into contact with the Guardians of the Galaxy.
Why It Could Be True: If Drew McWeeny's
report is to be believed, the movie truly does end with Hulk flying away from Earth, and it's pretty easy to draw the logical conclusion that he'd meet up with the Guardians (possibly in a post-credit scene), as this would provide an easy link between them and The Avengers, and potentially also give The Hulk something to do in Guardians Of The Galaxy 2.
Why It's Probably Not: On the other hand, this climax feels rather similar to the end of the original Avengers movie, and though certainly logical, it almost sound a little too sensible and clean to actually be true.