John Simm had told how filming on his new series, Prey, had to be halted after he injured himself.
The Bafta-nominated actor ripped a muscle in his leg while playing Detective Sergeant Marcus Farrow, who goes on the run to clear his name for his family's sake after being found at a murder scene.
He said: "We were filming a scene where Marcus is being chased through fields and ends up wading through a river. It was very cold, we were on about the third take of me clambering up this wet verge, and as I launched myself forward my foot slipped and I felt my calf muscle tear."
"I've never had any problems with my calf muscles before, and it wasn't as if I hadn't stretched and prepared correctly, so I guess it was just bad luck. I've never torn any muscle but there's a first time for everything!" he went on.
"It was frustrating, as we had to halt filming for a while as the muscle healed and I had physio, but I was raring to go when we resumed filming in the New Year and there were no more problems."
The high-octane three-part ITV thriller sees John, 43, doing "lots of running, hanging off bridges and climbing fences" and he admitted he had to get in shape for the part.
"It is a very physical role so I prepared by upping my gym work. When you hit your mid-forties it's a good idea to keep fitness levels up!" he said.
The actor also told how he could relate to the way his character felt, being a dad himself.
"Sometimes as an actor you have to put yourself in a horrible place to convincingly portray a certain emotion, it's not very nice but you have to draw from real life," he explained.
Prey which begins tonight (April 28) at 9pm on ITV, also stars Rosie Cavaliero, Craig Parkinson, Anastasia Hille and Adrian Edmondson.