Revealing mistake: When Khan and Spock are fighting on the garbage scow as it glides over San Francisco, you can easily see Spock's stunt double being beaten by Khan's stunt double. And vice versa.
Star Trek Into Darkness (2013)
1 revealing mistake - chronological order
Directed by: J.J. Abrams
Starring: Benedict Cumberbatch, Simon Pegg, Chris Pine, Karl Urban, Zoe Saldana, Anton Yelchin, Alice Eve, John Cho, Zachary Quinto
Factual error: At one point Khan threatens to target the Enterprise's life support systems which are located behind her "aft nacelle". The Enterprise doesn't have an aft nacelle; as the many exterior shots show, it has a port nacelle and a starboard nacelle. Khan a) is familiar enough with Starfleet ships to know this basic fact about the Enterprise, and b) can see its nacelles for himself on his own viewscreen while he's delivering this line. There is no "nacelle" housing the impulse engines. They are enclosed by the hull of the saucer section. (01:37:25)
Bones: Jim, you're not actually going after this guy, are you?
James T. Kirk: I have no idea what I'm supposed to do, I only know what I can do.
Trivia: As Kirk, Spock, and Uhura head to the shuttle bay for their mission to Kronos to capture Khan, Sulu orders crew to prepare the vessel that was confiscated in the Mudd incident. This is a reference to Harry Mudd, a roguish character who appeared in the original Star Trek series in the episodes titled,"I, Mudd" and "Mudd's Women." Harry Mudd, played by Roger C. Carmel, was the only non-regular character to appear in more than one episode on the original Star Trek series. Carmel was slated to reprise the role in Star Trek: TNG, but he died before the episode could be filmed. (00:44:25)
More questions & answers from Star Trek Into Darkness
Chosen answer: McCoy has no real idea how much blood he's going to need to bring Kirk back - given the catastrophic radiation damage to his body, there's every possibility that he might need multiple transfusions over a period of time, which would be much easier if Khan was still alive. Plus there's also the issue that killing Khan could well involve spilling some of the blood that McCoy so desperately needs. Bringing Khan in alive is the best way to maximise their chances.
Tailkinker ★