Duke Moosekian Duke Moosekian is the actor who portrayed Chief Gillespie in the fourth season episode . He filmed his scenes on Friday on Paramount Stage 8 . He was born as Shaun Duke Moosekian in the USA and graduated from the San Francisco Art Institute . He is the brother of actor , director and producer Vahan Moosekian . Television . Moosekian made his television debut in 1985 with an appearance in the sport drama " Heart of a Champion : The Ray Mancini Story " with Ray Buktenica and Lycia Naff . He had guest roles in " Dynasty " ( 1985 , with Joan Collins ) , " Cagney & Lacey " ( 1986 , with Dan Shor ) , " L . A . Law " ( 1986 , with Corbin Bernsen , Robert Costanzo , Stanley Kamel , and Scott Lincoln ) , and " Tour of Duty " ( 1989 , with Dan Gauthier and Noel De Souza ) . He also appeared in the television movies " Kate ' s Secret " ( 1986 , with Leslie Bevis ) , " Roses Are for the Rich " ( 1987 , with Anne Haney , Robert Picardo , Kate Mulgrew , Dendrie Taylor , and Thomas Knickerbocker ) , " Blown Away " ( 1990 , with David Selburg ) , " Before the Storm " ( 1991 , with Shelly Desai , Salome Jens , and John Rhys - Davies ) , " Line of Fire : The Morris Dees Story " ( 1991 , with Corbin Bernsen and Casey Biggs ) , " Desperate Choices : To Save My Child " ( 1992 , with Ron Canada , Bruce McGill , Bruce Davison , and Mary Kohnert ) , " Casualties of Love : The Long Island Lolita Story " ( 1993 , with Lawrence Tierney , Jack Kehler , Paddi Edwards , and Erick Avari ) , " Desperate Rescue : The Cathy Mahone Story " ( 1993 , with Clancy Brown , Jeff Kober , and Lindsey Haun ) , " Menendez : A Killing in Beverly Hills " ( 1994 , with Dakin Matthews , Dwight Schultz , Michael Durrell , J . C . Brandy , Matt McKenzie , Earl Billings , Richard Ortega - Miro , and David Selburg ) , " New Eden " ( 1994 , with Nicholas Worth ) , " Abandoned and Deceived " ( 1995 , with Bibi Besch , Rosemary Forsyth , Robert Hooks , Claudette Nevins , Patti Yasutake , and Gordon Clapp ) , " Dazzle " ( 1995 , with Bruce Greenwood , Natalija Nogulich , Joel Polis , and Susan O ' Sullivan ) , " The Invaders " ( 1995 , with Scott Bakula , Jack Kehler , Elinor Donahue , Lindsey Ginter , Rick Fitts , Don Pugsley , and Al Rodrigo ) , and " And the Beat Goes On : The Sonny and Cher Story " ( 1999 , with Jay Underwood and Vinny Argiro ) . Beside his work on television movies he made guest appearances in episodes of " Mancuso , FBI " ( 1990 , with Andreas Katsulas , Mark Margolis , and directed by Rob Bowman ) , " Doogie Howser , M . D . " ( 1990 , with James B . Sikking and Katy Boyer ) , " Doctor Doctor " ( 1990 , with Matt Frewer ) , " Growing Pains " ( 1990 ) , " Get a Life " ( 1990 , with Elinor Donahue , Zachary Benjamin , Brady Bluhm , and John Walter Davis ) , " Shades of LA " ( 1991 , with Brian Bonsall ) , " Stat " ( 1991 , with Casey Biggs , Wren T . Brown , Ron Canada , and Rudolph Willrich ) , " Matlock " ( 1992 , with David Froman , Jeff Hayenga , Franc Luz , David Spielberg , and Nick Tate ) , " Ellen " ( 1994 , with Douglas Price ) , " Silk Stalkings " ( 1993 - 1994 , with Mario Roccuzzo , Charlie Brill , J . C . Brandy , and Eric Pierpoint ) , " Courthouse " ( 1995 , with Bob Gunton , David L . Crowley , Kevin Scott Allen , Dan Gauthier , Jacqueline Kim , and Kenneth Tigar ) , " Pacific Blue " ( 1996 , with David L . Lander , Michael Cavanaugh , Dennis Christopher , Tim de Zarn , and Sam Hennings ) , " The High Life " ( 1996 ) , " NewsRadio " ( 1996 , with Stephen Root and Andy Dick ) , " The Burning Zone " ( 1997 , with Michael Harris , James Black , Andrew Kavovit , and Dennis Howard ) , " ER " ( 1996 and 1998 , with Bibi Besch , Claudette Nevins , Paul Dooley , Ann Gillespie , Tommy Hinkley , Penny Johnson , Lily Mariye , and director Babu Subramaniam ) , " Martial Law " ( 1999 , with Tom Wright and Tim Rigby ) , and " The Hughleys " ( 2000 ) . Further television guest roles include " JAG " ( 2000 , with Julie Caitlin Brown , Rif Hutton , and Kamala Lopez ) , " Gideon ' s Crossing " ( 2001 , with Rosalind Chao and Bob Clendenin ) , " NYPD Blue " ( 1994 and 2001 , with Gordon Clapp , Sharon Lawrence , Richard Lineback , Christopher Carroll , Greg Grunberg , Wayne Pere , and L . Sidney ) , " 24 " ( 2002 , with Penny Johnson , Billy Burke , Michelle Forbes , Freda Foh Shen , and Harris Yulin ) , " The Shield " ( 2003 , with Michael Jace , Jay Karnes , and Benito Martinez ) , " Dragnet " ( 2003 , with Erick Avari , Leon Russom , and Tim Lounibos ) , " She Spies " ( 2003 , with Pasha Lychnikoff and Faith Minton ) , " Eyes " ( 2007 , with Rick Worthy and Gregg Henry ) , " NCIS : Naval Criminal Investigative Service " ( 2007 , with Scottie Thompson and Susanna Thompson ) , and " Lie to Me " ( 2009 , with Kristen Ariza ) . Moosekian had recurring roles in " The Agency " ( 2001 - 2003 , with David Clennon , Ronny Cox , Wade Williams , Daniel Benzali , Faran Tahir , and Iris Bahr ) , " O . C . , California " ( 2006 , with Melinda Clarke , Autumn Reeser , Michael Nouri , Brandon Stacy , Chase Kim , and Daphne Ashbrook ) , J . J . Abrams ' " Alias " ( 2006 , with Rachel Nichols , Victor Garber , Leland Crooke , Troy Brenna , Jack Donner , Theo Kypri , and Amanda Foreman ) , " What About Brian " ( 2007 , with Amanda Foreman ) , " The Unit " ( 2006 - 2007 , with Abby Brammell , Tzi Ma , Conor O ' Farrell , Don McManus , Vyto Ruginis , Michael Cavanaugh , Carlos Lacamara , Annie O ' Donnell , and Robert Mammana ) , and " Prison Break " ( 2008 - 2009 , with Robert Knepper , Wade Williams , Cress Williams , Leon Russom , and Dan Sachoff ) . More recently he appeared in Brannon Braga ' s " FlashForward " ( 2010 , with John Cho ) , " The Mentalist " ( 2010 , with Marco Rodriguez and Leslie Hope ) , and " Terriers " ( 2010 ) and had a recurring role as Omar Shirazi in " 90210 " ( 2008 - 2010 , with Ann Gillespie ) . Film . Moosekian made his feature film debut in the comedy " Surrender " ( 1987 , with Iman and Bruce French ) , followed by supporting roles in the crime drama " Patriot Games " ( 1992 , with Ellen Geer , Fritz Sperberg , and Bob Gunton ) , the short film " Housewives : The Making of the Cast Album " ( 1994 ) , the action film " Flashfire " ( 1994 , with Louis Giambalvo , Mark L . Taylor , and Douglas Spain ) , the romance " One Fine Day " ( 1996 , with Barry Kivel ) , the drama " Entropy " ( 1999 ) , the horror thriller " Stigmata " ( 1999 , with Thomas Kopache , Ann Cusack , and Jack Donner ) , and the comedy " Hanging Up " ( 2000 , with Ethan Dampf ) . He appeared in the critically - acclaimed drama ( 2004 , with Virginia Madsen ) , lent his voice to the mystery thriller " Believers " ( 2007 , with Daniel Benzali , Cullen Chambers , and Rif Hutton ) , and appeared more recently in the short comedy " 00 : 24 " ( 2011 ) .