A clip from the movie “Iron Man 2” went viral on social media after Marvel fans discovered that billionaire Elon Musk made a cameo appearance alongside Robert Downey Jr. as Tony Stark.

Elon Musk is looking ... Studios’ 2008 film Iron Man, Mark Fergus, also previously named Musk as an inspiration for the titular character in the series. Musk had a cameo in the second ...