Director Matt Shakman has confirmed a new detail about The Fantastic Four: First Steps that puts a theory many fans have had about the film to rest. Ever since it was confirmed that First Steps would take place outside the MCU’s sacred timeline in an alternate 1960s retro-futurist reality, a popular theory that emerged online is that the film would feature cameos from other Marvel heroes that were closely inspired by their original Silver Age comic designs. With many of the most famous Marvel heroes having originated in the 1960s, this seemed like a fun idea to explore within this multiverse, a world that sees the Fantastic Four and other Marvel heroes in the period in which they originated.