While it remains to be seen whether actor Dan Stevens' decision to retire his "Downton Abbey" character Matthew Crawley was a smart one, it's definitely paid off for his overall health. 

Removed from the rather sedentary British aristocracy in "Downton," Stevens transformed himself for a new role in "The Guest," playing a former U.S. military solider hiding a violent secret. The 31-year-old says it took him three months and a daily block of time in the gym to pull off the physical look. 

"I worked very hard. I'm not a natural gym bunny and there was a lot of pain involved," he told the Guardian. "I was training for four hours a day for a month, and then we shot for two months and I continued that training. Aesthetically, it was surprising. I have never looked like that in my life. My wife was very happy."

In graduating to a cut figure, Stevens says he took control of his diet and lost more than 30 pounds. 

"It was pretty intensive," he told GQ UK. "I had to look very carefully at what I was putting in my body. It all felt pretty strict; a four-hours-a-day regime of gym and martial arts, various other physical training and also getting familiar with guns and ammo. I don't eat dairy, so my diet was incredibly protein heavy. Since then I've actually cut out meat altogether just for a bit to re-dress the balance."

While Stevens says he is thrilled to have achieved the look he was aiming for with the character, he's quick to add that he hasn't turned into a gym rat. 

"I'm not suddenly evangelical about it. If I had to do it for another role, I could do it again. I feel like I'm ready for anything. I had been coasting in a state of 'not much gym' for five years. And suddenly 'lots of gym'. And a bit of martial arts mixed in. And discipline. I'm not always good at that."

"The Guest" is now in theaters. Check out a trailer below. 

Related on MNN: