CHARLIE AND DON BUTT HEADS AFTER ONE OF CHARLIE'S COLLEAGUES IS ARRESTED BECAUSE OF HIS SUSPECTED TIES TO A TERRORIST GROUP, ON THE FOURTH SEASON FINALE OF "NUMB3RS," FRIDAY, MAY 16

Zeljko Ivanek ("24") Guest Stars as Special Agent William Fraley

"When Worlds Collide" - Don and Charlie find themselves in conflict over their differing beliefs as they investigate a case involving national security. Meanwhile, Megan faces a crisis of conscience and leaves the team, on the fourth season finale of NUMB3RS, Friday, May 16 (10:00-11:00 PM, ET/PT) on the CBS Television Network.

SERIES REGULARS:

Don Eppes: Rob Morrow
Charlie Eppes: David Krumholtz
Alan Eppes: Judd Hirsch
David Sinclair: Alimi Ballard
Megan Reeves: Diane Farr
Amita Ramanujan: Navi Rawat
Colby Granger: Dylan Bruno

GUEST CAST:

William Fraley: Zeljko Ivanek
Phil Sanjrani: Ravi Kapoor
Shane O'Hanahan: Shawn Doyle
Asha Rafiq: Meera Simhan
Shaza Rafiq: Tiya Sircar
Hadi Rafiq: Shan Ali
Benjamin Rajar: Nick Jaine
Max Flaherty: Paul Vincent O'Connor
CIA Officer: Kevin Symons
Cop: Michael Balsley
Attorney: John Hawkinson
Sport Coat #1: David Valcin
The Real Hassan: Mazari Barber Ali
Kaleen Rafiq: Roman Mitichyan

WRITTEN BY: Executive Producers Cheryl Heuton & Nicolas Falacci

DIRECTED BY: John Behring

RATING: TV14-LV