Matt Smith has told of his shame at stripping naked to swim in the freezing sea during his first film scene with Eva Green.

The 27-year-old Doctor Who actor plays Thomas, the late husband of Eva’s character, who she seeks to clone, in sci-fi thriller Womb.

Matt told The Sun: “We were on the north German coast and the script called for me to run into the Baltic without any clothes on, in the middle of b****y winter. It was the coldest I’d ever been and, of course, it just so happened to be my first scene with Eva.

“I had to get out of the water and do the whole thing in front of her stark b*****k naked.

“That’s not a good lot for any man, let me tell you.”

Matt, who makes his Doctor Who debut on BBC One on April 3, was so cold he collapsed.

He explained: “They said I could use a double, but I’d worked myself up to do it so I went into the sea three times.

“The next shot we did, we were running along the beach and I was so frozen I couldn’t move. I just hit the deck,” he said.