(NOTE LANGUAGE) The Time Traveler's Wife debuts Sunday night on HBO, based on the best-selling book by Audrey Niffenegger.
The time-travel love story stars Theo James as Henry, the guy who moves through time, and Rose Leslie as his wife, Clare. James tells ABC Audio it's all about what would change -- or not change -- if you could travel through time.
"Time travel is an interesting concept, not only for changing where you're going to go, but also imagining what you could have changed in the past as well," he explains. "...Would you change things in your life or are all the things that happen in our lives, mistakes, warts and all, did they make us the person that we are?
There are several rules to time travel within the story, and the first, says James is that "for Henry, things happened to him once. So in the larger scheme, there's a cycle of time that's going like that essentially, and the main Henry's in the middle of it and these things happen to him once."
Additionally, Henry is "brought back to moments that are significant to him and he visits people that are significant to him in life," which James explains "is a metaphor for, you know, traumatic events in our history... and how we perhaps would visit them more than the more mundane ones."
Another rule is that Henry "can only travel within his lifespan" -- or does he? James and Leslie can't seem to agree.
"It's a bulls*** rule I guess," jokes Theo.
"No, it's not a bulls***. rule. It's not," Leslie interrupts. "I'm thinking of, but I'm going to be giving away a spoiler. But I have a line whereby you can only time travel within your lifespan, but only occasionally do you go beyond that."