Kevin Bacon stays in character all day long while filming serial killer drama The Following and only switches off when he leaves the set.

The actor plays a troubled agent hunting down murderers in the Tv series, and insists the dark subject matter makes it impossible to be his normal self during breaks on set.

He tells Britain's Ok! magazine, "I have to work on that (relaxing). The one thing I can't do is switch it off and on over the course of the day like some people can. They say cut and turn to the person and say, 'Anyway, blah blah blah, what time is lunch?' But I have to kind of stay in it during the day, then afterwards I try and walk away from it. What helps is to be with my wife and kids, to have a nice meal, a glass of wine, to watch something that's not the show or take a hike to shake it away a bit. It's always a good idea in terms of mental health."

Bacon also admits he feels relieved not to be playing James Purefoy's role as the show's lead killer, adding, "It is nice! I certainly had those (villainous) options more in the movies and I didn't want to be that guy. I think James Purefoy is fantastic, so it was a good decision."