Dax Shepard directed 'CHIPS' in the nude.

Dax Shepard and Kristen Bell

Dax Shepard and Kristen Bell

The 42-year-old actor-and-filmmaker had to strip off for a scene in the upcoming action comedy - which is based on 1970s TV show 'CHiPs' - and though he initially concealed his modesty when having to step behind the camera for his directorial duties, he eventually shed his inhibitions as well as his clothes.

He said: "I think in the morning I started off putting my robe on in between every take when I would go over and talk to the camera department.

"But, as less and less time was available to us, I found that I was not putting my robe on between takes and I'd be like, 'Wow, I haven't put on any clothes on in three or four hours and everyone seems to be fine with it.'

"By the way, that was the second day of filming, so I was relative strangers with most of the people, except for my department heads. The rest of the people were new faces.

"And [Michael] Peña and I didn't know each other, so that was day two for him as well."

Because the scene was quite tricky to film technically, Dax - whose wife Kristen Bell also stars in the film - admits he didn't have time to worry about how his naked body looked on camera.

Asked if he wanted to make sure he looked good in the scene, he told 'Entertainment Tonight': "I probably would have been thinking about it more if it wasn't such a technical scene to shoot.

"It sounds silly to say that, but of all the different stunts, that was by far in the top three hardest things just to film correctly.

"I was in a harness on a trolley with an air ratchet and I got slammed into the wall.

"There are a lot of elements involved with that, so I lost track of [the nudity].

"If I was just there as an actor, I would have been thinking about it a lot, like, 'Oh, I gotta do push-ups. I gotta do this or that', but the much bigger priority for me was making sure I wasn't screwed in the editing room."