Lie to Me debuts tonight on Fox and is based on the work of Paul Ekman, who has studied lie-detection techniques for over 50 years.

In other words: No, contrary to comparisons, it's not a knock off of CBS' The Mentalist.

Tim Roth says his co-stars on the new drama are aware of The Mentalist, but he isn't worried about being pigeon-holed as a copy cat.

"I haven't seen the show. I haven't seen The Mentalist," Roth told TV Guide. "I think the proof is in the pudding. ... We are what we are."

Roth portrays lays Cal Lightman on the series. He's an expert of reading people's faces and body language to tell whether they're lying.

Similarly, The Mentalist stars Simon Baker as an investigator whose ability to read people is so powerful he appears capable of reading minds.

However, Lie to Me executive producer Brian Grazer points to a major difference between the shows: science.

"I'm not really interested in The Mentalist's process," Grazer said. "I mean it might be good — I mean I think it is good, it's doing really well — (but) I'm actually interested in whether people are telling the truth."

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.