In the second film of the revived 'Star Trek' movie franchise, J.J. Abrams made the questionable decision to go for something close to a remake of 'Star Trek II: The Wrath of Khan' instead of making an original film. He raised even more eyebrows when he cast 'Sherlock' actor Benedict Cumberbatch as the villainous Khan - Cumberbatch is a fine actor, but the original Khan played by Ricardo Montalban was a muscular hulk of a man - perfect for the genetically-engineered superhuman than Khan is supposed to be.
The plan makes a little more sense when you find out that it was originally Benicio Del Toro playing Khan; Del Toro is a little older and bulkier, and so would have probably been more convincing in the role. Unfortunately, the production company and Del Toro couldn't reach an agreement on how much the actor ought to be paid for his performance, and so Cumberbatch stepped in at the last minute.