Main Characters Captain Harmon "Harm" Rabb Jr., USN 227 main appearances Captain Bud J. Roberts Jr., USN 96 main appearances Lieutenant Colonel Sarah "Mac" MacKenzie, USMC 99 main appearances Rear Admiral A.J. Chegwidden, USN 86 main appearances Lieutenant Harriet Sims-Roberts, USN 50 main appearances Yeoman First Class (YN1) Jason Tiner, USN 49 main appearances Lieutenant Commander Mic Brumby, CSC, RAN 40 main appearances Gunnery Sergeant Victor Galindez, USMC 37 main appearances Lieutenant Loren Singer, USN 19 main appearances Special Agent Clayton Webb 15 main appearances Commander Peter Ulysses "Sturgis" Turner, USN 20 main appearances Lieutenant, Junior Grade Megan "Meg" Austin, USN 20 main appearances Legalman First Class (LN1) Jennifer "Jen" Coates, USN 10 main appearances Midshipman Third Class Michael "Mikey" Roberts, USNA 3 main appearances Rear Admiral Thomas "CAG" Boone, USN 3 main appearances Major General Gordon "Biff" Cresswell, USMC 4 main appearances Commander Caitlin "Kate" Pike, USN 2 main appearances Lieutenant Gregory Vukovic, USN 2 main appearances
Recurring Guest Characters Rear Admiral Thomas "CAG" Boone, USN 2 guest appearances Major General Gordon "Biff" Cresswell, USMC 1 guest appearances Catherine Gale 5 guest appearances Admiral Drake 4 guest appearances Mark Falcon 4 guest appearances CAPT Tobias Ingles 4 guest appearances Col. Clifford Blakely 4 guest appearances CAPT Johnson 4 guest appearances Senator Edward Sheffield 4 guest appearances Mattie Grace Johnson 4 guest appearances Meredith Cavanaugh 4 guest appearances Captain Owen Sebring 4 guest appearances CDR Carpenter 3 guest appearances Chuck DePalma 3 guest appearances Commander Caitlin "Kate" Pike, USN 1 guest appearances Trish Burnett 3 guest appearances LT Dalton "Boomer" Jonas 3 guest appearances LT "Tuna" Medwick 3 guest appearances Dr. Lawrence Gettis 3 guest appearances Little A.J. 3 guest appearances ⇤ « 1 2 3 4 5 6 7 8 9 10 » ⇥