Director Doug Liman got his start making breakthrough independent films such as Swingers and Go but he may be best known to most moviegoers as the director of Mr. and Mrs. Smith and The Bourne Identity. Despite his last few films bearing expensive studio price tags, he assures me that his filmmaking process is still grounded in his independent roots.

His latest endeavor is Edge of Tomorrow, starring Tom Cruise and Emily Blunt. It’s an action-adventure story blended with touches of comedy and science-fiction, but to hear Liman describe it, the film is a war movie through and through.

Based on the Japanese novel All You Need Is Kill, the film takes place during an alien invasion. Cruise headlines the film as a military mediator with no combat experience thrust into battle by his superiors only to discover a unique loophole. Upon confronting the alien enemy on the battlefield, Cruise inadvertently absorbs their power and is able to relive the same day over and over again until he gets it right. It’s a video game scenario where if Cruise dies in combat he can regenerate and try again, each time rising stronger and smarter than the time before and with a different strategy to defeat the aliens.

On a recent promotional trip to San Francisco, we spoke to Doug Liman about taking on the difficult challenge of making Edge of Tomorrow. The following is a transcription of that conversation.

Q: What shaped your interest in this film?

Doug Liman: I thought the device was awesome. A movie where the main character has the ability to repeat the same action sequence, in this case an epic war battle, over and over again sounded amazing. I wanted to show this battle from different points of view and see if one soldier could make a difference.

Q: How easy or difficult was it to keep track of all the different timelines and scenarios on set?

Liman: There’s a Rashomon aspect to Edge of Tomorrow, so once we figured out what a normal day would look like for Tom Cruise’s character, in was easier to figure things out because you get to see the same thing from different points of view. But in this case all of those points of view are Tom’s, you never see him go to the same place or do the same thing twice. And also, after a while it was becoming so much fun to kill Tom’s character in a Road Runner or Wile E. Coyote kind of way that we added a lot more of that to the script. I haven’t had this kind of freedom to improvise and workshop with my actors since Swingers.

Q: How much of your stunts were practical as opposed to computer generated?

Liman: We did real stunts. You would think that with suits of armor and aliens it would be easier to just go with computer effects, but I wanted everything to look real. It was a decision I cursed every day during production to do real stunts and build real suits of armor, but during editing and now looking back, I couldn’t be prouder of that decision.

Q: One of the biggest surprises in the film is the amount of humor, mostly at the expense of killing Tom Cruise over and over again.

Liman: Or just seeing Tom in way over his head.

Q: Right! How did you find the right comedic balance in telling this story?

Liman: I was making an honest war movie. So as long as the humor was character driven it made sense. I didn’t want the action or the comedy to go to a silly place, everything had to be real for me. That’s why I don’t call this film a science-fiction film. I call it a war movie. When you think of a war movie you think of real characters, real situations and high stakes. Those are the feelings I want you to have when you watch Edge of Tomorrow. And part of the fun of this movie is taking Tom, who is one of the biggest movie stars on the planet and always playing very confident characters, and putting him way over his head from the beginning of the film.

Q: This is purely cosmetic, but what went into the decision to change the film’s original title of All You Need Is Kill to Edge of Tomorrow?

Liman: The first thing I did when I came on board the movie was make the decision of casting Tom and Emily and then realizing that I wanted to bring a lot more humor to the story and that original title didn’t reflect that. The film’s not a comedy but it needed to have a title that felt consistent with the action-comedy tone I was going for.

Q: Obviously the original source material has the original title but I also remember reading that the Sandy Hook shootings had a part in Warner Brothers changing the title. Is that true?

Liman: No. If I hadn’t wanted to change the title from the beginning I’m sure they would’ve stepped in and said they didn’t want to release a summer movie with the word kill in it. (laughs) But that original title is much darker than the movie I was setting out to make.

Q: It’s funny you mention that because the film is rated PG-13 and a lot of the kills are either off-screen or there’s very little blood shown. Was there ever a rougher R-rated cut of the film?

Liman: No. The first time we submitted it to the MPAA ratings board we got a PG-13. But at the same time we never had a rougher cut of the film because if we went too far with the kills you’d stop having fun with the movie. I wanted you to laugh when Tom was killed. I wanted real stakes for his character, but I also wanted you to laugh.

Q: Is Splinter Cell still next for you?

Liman: I’m not sure yet.

Q: How far along are you in the process?

Liman: When it comes to studios and making movies, our business isn’t like other businesses where you make a plan and stick to it. You always need a few irons in the fire just in case one of them doesn’t work out. I have a really great take on Splinter Cell and I haven’t done a spy movie since I created the Bourne franchise, so I’m really excited about this one. I also have other projects that I am equally passionate about, you just never know in what order you’re going to make them.

Q: Are any of those an independent project taking you back to your Swingers roots?

Liman: Swingers occupies a very special place in my heart but also a very terrifying place in my heart as well. On Swingers we got lucky every day of that shoot. We had $200,000 to make that film so there was no margin for error and every day there was some calamity that should’ve ground the film to a halt. But through sheer perseverance and an incredible amount of luck we got through that.

Q: Which of your films do you feel is the most underrated?

Liman: Go. In many aspects I am so proud of Go, but I’m also proud of myself for seeing it through. After Swingers everyone was telling me to make a studio film and I bucked the system and said I’m going to make another independent film instead and it’s the film I’m most proud of.

Q: Since you’re getting asked a lot of questions on this press tour, what’s the one question you wish would go away?

Liman: The question I get asked the most is, “What’s it like working with Tom Cruise?” but since I had the most extraordinary experience working with him I like talking about that because I don’t always have the best experiences with people I work with. But if someone asks me, If you had any day to relive over and over again, which one would it be? that’s the question I dodge. (laughs)

Edge of Tomorrow is now playing in theatres nationwide.