"There wasn't enough nudity," James quips on the latest episode of EW's Screen After Reading podcast.

To make The Time Traveler's Wife, Theo James had to bare his soul — and his butt. A lot.

The HBO series, which completed its first season Sunday, tells the story of time traveler Henry De Tamble (James) and the love of his life, Clare Abshire (Rose Leslie), as they fall for each other across space and time.

Henry has a genetic disorder that causes him to time-travel to unknown places and moments without warning. And to make matters worse, no matter where or when he arrives, he's always naked. Hence the profusion of sightings of James' rear end.

"There wasn't enough nudity," James jokes on the latest episode of EW's Screen After Reading podcast. "No, it's a part of the DNA of the book. What I liked about it is the nudity is dangerous. He's thrown out of time, and it expends a lot of energy. It depletes him. It's an affliction, an illness that he has to deal with. I always felt like it's an epileptic fit times 100, where it's a real shock to his body."

"When [Henry] falls out of time, he doesn't know where he is, when he is," James adds. "He's naked, which has its problems, but also in a practical sense, he has nothing on him. Nothing to protect himself with. Nothing to help himself with. He has to be the ultimate survivor, and that part of it makes it dangerous and propulsive, as opposed to a fun romantic mechanism. It's something that he has to overcome or survive over time."

The team behind 'The Time Traveler's Wife' joins EW's 'Screen After Reading' podcast
The team behind 'The Time Traveler's Wife' joins EW's 'Screen After Reading' podcast
| Credit: Barbara Nitke/HBO

HBO's Time Traveler's Wife marks the second adaptation of Audrey Niffenegger's best-selling 2003 novel, following a 2009 film starring Rachel McAdams and Eric Bana. But Steven Moffat (Sherlock, Doctor Who) spent a long time believing it would make a far better TV show.

"Audrey's version of time travel, you have to understand the rules," Moffat says. "That would take more than half a movie, by which time you've got almost no time to talk about what the book's actually about: good marriage and healthy love over time. The time travel is a device, a prism though which to see that, and a way of reminding you that love is inextricably linked to loss."

Niffenegger says that when she was first writing the book, she was intent on crafting a version of time travel that was about the frailty of time rather than the elasticity. "It's important that he be time-traveling involuntarily," she notes. "That he is not just some jerk running away all the time and having adventures without his sweetie. The race to decode the human genome was much in the news at the time [I was writing], and I thought, 'That's it, it's a genetic thing.' You can't control it. It just dumps him wherever, naked, and the other really important rule is that he can't go back and change things. It's not Back to the Future, and that is the difference between tragedy and comedy."

Moffat, who knows a thing or two about time travel after many years writing for Doctor Who, was mesmerized by Niffenegger's version of time travel and the ways in which it might hew closer to reality if such a thing ever did exist.

"Given that time travel is nonsense, it sounds so much more realistic than any other version," he says. "The whole notion of changing history, of Doctor Who popping back and fixing things, it's such nonsense. It only happens once. Everyone's used to the version where you can go back and fix things, and this is literally a story about no second chances. Today's what you've got. Right now is what you've got. I reveled in it because it's so well done in the book; you buy into it as a credible thing because it's presented to you as a difficulty. He's naked, he's running, it makes him vomit. It's not Doctor Who popping out of the police box, is it?"

Listen to the latest episode of Screen After Reading below for more from the team behind The Time Traveler's Wife.

Check out more from EW's Screen After Readingfeaturing exclusive interviews, analysis, and more as we dive into the art of bringing books to the screen.

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