A DEADLY SHOOTING AT A LOCAL HIGH SCHOOL LEADS THE FBI TO A SURPRISING SUSPECT, ON "NUMB3RS," FRIDAY, APRIL 7

"Dark Matter" -- Don and his team investigate a school shooting only to be surprised with one of the suspects, on NUMB3RS, Friday, April 7 (10:00-11:00 PM, ET/PT) on the CBS Television Network. Peter Ellis directed the episode written by one of the co-executive producers, Don McGill.

As Don and his team investigate the motive behind two students' deadly school shooting, Charlie uses the school's radio frequency identification system to track the shooters' movements through the school's hallways. But when Charlie notices an abnormal pattern, Don and his agents reevaluate the evidence and discover an unlikely third participant.

Don Eppes: Rob Morrow
Charlie Eppes: David Krumholtz
Alan Eppes: Judd Hirsch
David Sinclair: Alimi Ballard
Larry Fleinhardt: Peter MacNicol
Megan Reeves: Diane Farr
Amita Ramajuan: Navi Rawat
Colby Granger: Dylan Bruno
Paul Elins: Nathan William Gumke
Justin Price: Ben Cambell
Karen Camden: Leighton Meester
Becky Flynn: Kate Linae
Jon Northrup: Rob Moran
Gregory Dietrich: Jesse Head
Marlene Stallworth: Mary Gordon Murray
Laura Price: Christine Estabrook
Joan Camden: Marin Mazzie
Jake Porter: Daniel Booko

RATING: To Be Announced