The actor returns to the role that made him famous and dishes on how he remembers his crazy lines

The ‘Batch is back!

Benedict Cumberbatch, once the Internet’s boyfriend and now an Oscar-nominated global sensation, has returned to the role that initially broke his career – the charming, asexual, modern day Sherlock Holmes.

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In between attending awards shows in Hollywood for his role in The Imitation Game, the newly engaged actor has been seen filming in London with costar Martin Freeman for a one-off Sherlock special set to air later this year.

So how does the actor manage to remember the crazy, rapid-fire lines that his Holmes character spews forth when making his deductions?

“There are two things,” Cumberbatch tells PEOPLE. “I memorize them very painstakingly and slowly. And I try to exercise, and stay off the cigarettes, booze and caffeine when filming, so I’ve got this good, healthy oxygenated blood and can think fast.”

Still, even a three-time Emmy winner and classically trained actor like Cumberbatch can have some trouble with the lines from time to time.

“There’s always a moment when I get behind and I’m having a messy day, and I’m just kind of going, ‘Sorry . ‘ But by and large, you have to be really disciplined,” he says.

Cumberbatch, who recently announced he’s expecting his first child with his fiancée, Sophie Hunter, also says the lines can be harder to do depending on the season they’re shooting.

“It can be hell when you’re standing on the side of the Thames in January with the winds … you can’t even move your jaw, so trying to do one of the long passages of deduction is really physically hard,” he says. “You have to warm up, remember to use your diaphragm.”

And shooting in the studio can be equally tough. “It’s really hot with the huge studio lights. When it comes to speaking fast, you really just can’t be tired or unhealthy in any way, or it’s going to be that much more work for you.”

And one of his preferred ways to stay in shape? In the great outdoors.

“I love hiking,” he says. “It’s great to get away in nature. It’s grounding. I go up to the country a lot, but I also love the coasts. We’re shooting Richard III, and it’s been the most amazing heritage tour in the English countryside, with all the castles and manor houses and nunneries. It’s stunning.”

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