| Character Name | Actor Name | Source | Character Description |
| Captain Hank Stanley | Michael Norell | Emergency! | Captain, Station 51, LA County |
| Dixie McCall, RN | Julie London | Emergency! | Trauma nurse, Rampart General |
| Engineer Mike Stoker | Mike Stoker | Emergency! | Engineer, Engine 51 |
| FF/Paramedic Johnny Gage | Randolph Mantooth | Emergency! | Paramedic, Squad 51 |
| FF/Paramedic Roy DeSoto | Kevin Tighe | Emergency! | Paramedic, Squad 51 |
| Firefighter Chet Kelly | Tim Donnelly | Emergency! | Firefighter, Engine 51 |
| Firefighter Marco Lopez | Marco Lopez | Emergency! | Firefighter, Engine 51 |
| Joe Early, MD, FACS | Bobby Troup | Emergency! | Trauma surgeon, Rampart General |
| Kelly Brackett, MD, FACS | Robert Fuller | Emergency! | Trauma surgeon, Rampart General |
| Lt. Bud Roberts | Patrick Laboryteaux | JAG | Navy JAG lawyer |
| Gunnery Sgt. Victor Galindez | Randy Vasquez | JAG | office staff, JAG HQ |
| Lt. Cdr Harmon Rabb | David James Elliott | JAG | Navy JAG lawyer |
| Lt. Harriet Roberts | Karri Turner | JAG | office staff, JAG HQ |
| Maj General Biff Creswell | David Andrews | JAG | Judge Advocate General of the Navy after AJ Chegwidden's retirement |
| PO Jason Tiner | Chuck Carrington | JAG | Yeoman, JAG HQ |
| PO Jennifer Coates | Zoe McClellan | JAG | Yeoman, JAG HQ |
| Rear Admiral A.J Chegwidden | John M. Jackson | JAG | Judge Advocate General of the Navy |
| Sarah MacKenzie Rabb | Catherine Bell | JAG | Marine JAG lawyer |
| Colonel Sherman T Pottter, MD | Harry Morgan | M*A*S*H | Head surgeon, MASH 4077, Korea |
| Fr. Francis X. Mulcahy | William Christopher | M*A*S*H | chaplain, MASH 4077, Korea |
| Hawkeye Pierce, MD | Alan Alda | M*A*S*H | trauma surgeon, MASH 4077, Korea |
| Margaret Houlihan Pierce, RN | Loretta Swit | M*A*S*H | head nurse, MASH 4077, Korea |
| Thomas Magnum | Tom Selleck | Magnum PI | former Seal, PI in Hawaii |
| Abby Sciuto | Pauley Perrette | NCIS | forensics investigator, NCIS |
| Ducky Mallard, MD | David McCallum | NCIS | medical examiner/forensic psychologist, NCIS |
| Special Agent Leroy Jethro Gibbs | Mark Harmon | NCIS | special agent lead investigator, major crimes, NCIS |
| Special Agent Timothy McGee | Sean Murray | NCIS | special agent, major crimes, NCIS |
| Special Agent Tony DiNozzo | Michael Weatherly | NCIS | special agent, major crimes, NCIS |
| Special Agent Ziva David | Cote de Pablo | NCIS | special agent, major crimes, NCIS; former officer in the Mossad |
| Hauptmann Hans Dietrich | Eric Braeden | Rat Patrol | Captain in Afrika Korps, WWII |
| Sgt. Jack Moffitt | Gary Raymond | Rat Patrol | Sergeant, Royal Scots Greys, WWII |
| Pvt. Mark Hitchcock | Larry Casey | Rat Patrol | Private, US Army, WWII |
| Sgt. Sam Troy | Christopher George | Rat Patrol | Sergeant, US Army, WWII |
| Sgt. Tully Pettigrew | Justin Tarr | Rat Patrol | Private, US Army, WWII |
| Colonel Jack O'Neill | Richard Dean Anderson | Stargate SG-1 | Colonel, USAF special operations; later promoted to General |
| Major Samantha Carter | Amanda Tapping | Stargate SG-1 | Major, USAF special operations, laer promoted to Colonel |
| Andrea Miller | Katie Mitchell | The Cape | PAO, Cape Canaveral |
| Major Caitlin Grayson, USAF | Wendy Kilbourne | The Cape | space shuttle pilot |
| Capt. Zeke Beaumont, USAF | Cameron Bancroft | The Cape | astronaut in training |
| Col. Henry "Bull" Eckert, USAF | Corbin Bernsen | The Cape | Head astronaut, shuttle program |
| Col. Jack Riles USAF | Adam Baldwin | The Cape | space shuttle pilot, later mission commander |
| Curtis Beaumont | Michael Hartson | The Cape | astronaut in training |
| D.B Woods | David Kelsey | The Cape | astronaut in training |
| LtCdr Barbara DeSantos, USN | Bobbie Phillips | The Cape | astronaut in training |
| Maj. Reggie Warren, USMC | Bobby Hosea | The Cape | astronaut in training |
| Noah Riles | Nick Corirossi | The Cape | Jack Riles's son |
| Peter Engel | Chad Willet | The Cape | astronaut in training |
| Tamara St. James | Tyra Ferrell | The Cape | mission specialist |