Mazzie's official website says the actress will play Joan Camden on the April 7 broadcast of the crime drama. The episode, which is entitled "Dark Matter," will air at 10 PM ET; check local listings. "Numb3rs," according to the CBS website, "is a drama about an FBI agent who recruits his mathematical-genius brother to help the Bureau solve a wide range of challenging crimes in Los Angeles. The two brothers take on the most confounding criminal cases from a very distinctive perspective." Rob Morrow and David Krumholtz co-star.

A three-time Tony Award nominee for her performances in Kiss Me, Kate; Ragtime; and Passion, Marin Mazzie's other theatrical credits include Into the Woods, Big River, The World Goes 'Round, the City Center Encores! production of Out of this World and Off-Broadway's The Trojan Women: A love Story, where she met husband Jason Danieley. Mazzie also starred in the London production of Kiss Me, Kate, where she earned an Olivier Award nomination for her work.

Visit www.cbs.com for more information.