Lie detector Roth: 'I try not to know too much'

British star Tim Roth says he doesn't take home his latest role, lie detection expert Cal Lightman, which can only be a good thing for his family.

Tim stars in Fox series Lie to Me, which screens on Sky1 in the UK, about the world's leading deception detection expert, a man who can tell by gestures and facial expressions exactly what someone is really thinking.

Tim, 47, told CNN he tries not to use the techniques off the set: "I try not to know too much, because it actually is quite extraordinary. When you watch politicians on TV, you can use the stuff that Paul does to see if they're lying or not. I try not to take it home."

The Paul he's talking about is Dr Paul Elkman, a leading specialist who reads clues embedded in the human face, body and voice to expose the truth in criminal investigations.

Roth says Dr Ekman can be intimidating. "He makes me very, very nervous, Paul, you know... I mean, he's the sweetest man, as sweet as can be, but when he's around, you feel like your acting is really being judged."

Lie to Me premieres on Sky1 on Thursday, May 14, at 10pm.