Star Trek into Darkness‘ J.J. Abrams explained why Khan was chosen as the villain and how the idea of using Khan’s blood to save Kirk came about.
Some fans expected a reboot to explore new stories, but Abrams wanted to explore Khan further.
“I think the thing was that Khan really is the most iconic villain of the series,” Abrams said, “and it felt like an opportunity to see another side of Khan and to something that, like the first film did, use elements that people were familiar with but in a new [way].”
Using Khan’s blood to save Kirk was an idea that came out of the events of the beginning of the film, although that had not been originally planned. “Well, it’s funny,” said Abrams, “we had this idea in the beginning of the film of this girl who is sort of being brought back into good health as a means of coercing her father to do something horrific, and it was sitting there. And we knew we wanted to do something that was going to kind of push Kirk to a limit where he was tested in a way he never had been before where he really had to appreciate the kind of chair that he was sitting in. And it ended up just coming out of realizing that we had this thing that was sitting there that was already set up in the movie.
“The idea for me with Khan that was so powerful was this was a sort of monster that we made – he was someone who, having been sort of genetically engineered and banished, he was someone who just like Kirk, loved his crew, and would do anything for them. And we realized that Kirk and Khan were very much in a similar position, and then finally we put them in a situation where you really question, can I trust him? Can I work with him at all? That to me was a fun thing, especially after the first movie where we had a wonderfully-performed bad guy, but a sort of simpler one, where it was just about a raving, vengeful, angry Romulan. So it was a fun thing to have a character that was able to have illuminating, deep, emotional, unexpected conversations.”
What’s next for the crew of the Enterprise? “It’s a valid argument that it’s about time for them to go off and discover and see things that have nothing to do with what we’ve seen before, and I think we’ll always have some overlap,” said Abrams. “But I’m excited about the next chapter.”
Source: Comic Book Resources