Writer-director Christopher McQuarrie revealed that the conclusion of Mission: Impossible - Dead Reckoning Part One was a topic of great concern for star Tom Cruise during production. According to McQuarrie in a recent interview with Total Film magazine, Cruise literally lost sleep over it, upset over the possibility of a cliffhanger ending.

"Where we ended the movie was always where we were going to end it," McQuarrie said. "How we ended the movie was a big, big mystery for us. It kept Tom awake at night throughout production. He would come in all the time and say, 'This can't be a cliffhanger, it's got to be satisfying.' The audience has to feel a sense of completion."