It was perhaps the biggest talking point of 'Star Trek Into Darkness'.
But now director JJ Abrams has said that he regrets keeping Benedict Cumberbatch's true character identity a secret.
Abrams, not to mention Cumberbatch and several of the other cast, consistently denied that he was playing Khan, the character made famous by Ricardo Montalban in 'Star Trek II: The Wrath of Khan'.
Instead Cumberbatch was given the alias 'John Harrison'.
Abrams says that the decision was perhaps a poor choice with hindsight.
“It was so important to the studio that we not angle this thing for existing fans,” Abrams told MTV.
“If we said it was Khan, it would feel like you've really got to know what 'Star Trek' is about to see this movie. That would have been limiting.
“I can understand their argument to try to keep that quiet, but I do wonder if it would have seemed a little bit less like an attempt at deception if we had just come out with it.
“The goal was to not ruin it for anyone who wanted to go see it, but the fact is it ended up, I think, coming off like we were being coy, or we were acting like we were more clever than we are or something.
“The truth is, I think it probably would have been smarter just to say upfront, 'This is who it is'.”
The reveal did indeed annoy fans, who were told rather flatly all along that their presumptions were wrong.
Elsewhere, Abrams broached the subject of whether Joe Cornish - known best perhaps in the UK for one half of comedy duo Adam and Joe, but now having co-written Steven Spielberg's 'Tintin' movie – will be directing 'Star Trek 3'.
“I don’t know if Joe Cornish is the guy,” he said. “My guess is that’s up in the air. I adore him and love him and can’t wait to see what he does next. Hopefully it will be Star Trek. Whatever it is, he’s brilliant. 'Attack the Block' was one of my favorite movies of the year when it came out.”