Mekhi Phifer is set to guest-star on Lie to Me in a two-episode arc starting Wednesday, May 6 (8:00-9:00 PM ET/PT) on FOX. Phifer, who begins production today, will play Ben Reynolds, an FBI agent who partners with Lightman to track down a serial rapist terrorizing the Washington, DC area. In the season's second to last episode, Reynolds, having spent the last six months pursuing the elusive criminal, assists The Lightman Group in solving their toughest case yet.

Perhaps best known for his starring role on ER, which garned him two NAACP Image Award nominations, Phifer is also known for his many successful feature films. He began his acting career in Spike Lee's Clockers and then went on to star in such films as 8 Mile opposite Eminem, O opposite Josh Hartnett and Julia Stiles as well as Soul Food with Vanessa Williams. Phifer's other television credits include The Tuskegee Airmen, Subway Stories: Tales from the Underground, Brian's Song and Carmen: A Hip Hopera. Phifer earned an additional NAACP Image Award nomination for the cable film A Lesson Before Dying.

Lie to Me, the No. 1 new series of the season among Adults 18-49, stars Tim Roth as Dr. Cal Lightman, the world's leading deception expert who studies facial expressions and involuntary body language to discover not only if someone is lying, but why. Based on the real-life scientific discoveries of Dr. Paul Ekman, the series follows Lightman and his team of deception experts as they assist law enforcement and government agencies to expose the truth behind the lies.

Samuel Baum, Brian Grazer, David Nevins and Steven Maeda serve as executive producers on the series, which is produced by Imagine Television and 20th Century Fox Television.