David James Elliott Lt., Lt. Cmdr. Harmon "Harm" Rabb, Jr. Actor Catherine Bell Maj., Lt. Col. Sarah "Mac" MacKenzie Actor Patrick Laborteaux Lt. j.g., Lt. Bud Roberts Actor Karri Turner Ensign, Lt. j.g. Harriet Sims Actor Scott Lawrence Cmdr. Sturgis Turner Actor Zoe McLellan Petty Officer Jennifer Coates Actor Chris Beetem Lt. Gregory Vukovic Actor Chris Johnson Guest Star Paul Schulze Guest Star Thomas Vincent Kelly Guest Star Derek Webster Guest Star Jason Grutter Guest Star Patrick St. Esprit Guest Star DeVaughn Nixon Guest Star Mel Harris Guest Star Bob Brownstein Guest Star Danneel Ackles Guest Star Randy Oglesby Guest Star John Walcutt Guest Star Donald P. Bellisario Executive Producer Charles Floyd Johnson Executive Producer Stephen Zito Executive Producer, Writer Mark Horowitz Executive Producer Bradford May Director