The character was created by Donald P. Bellisario, as a work for hire for Paramount Television, in the script for the JAG pilot episode, which was filmed and then aired by NBC on September 23, 1995.

[3][4][7] On Christmas Eve 1969, while flying an Iron Hand mission, Harmon Rabb, Sr. was shot down over North Vietnam and was considered MIA.

[8] Later on, Harm met his half-brother, Sergeant Sergei Zhukov (Jade Carter) a helicopter pilot in the Russian Army, who was accused of selling weapons to Chechen rebels.

In one episode, he met Jenny Lake (played by Catherine Bell) who was present on the USS Ticonderoga when his father was shot down (and had been the fiancée of a Marine aviator who was KIA).

[6] On another Christmas Eve, he invited one of his father's former squadron buddies Rear Admiral Thomas Boone (Terry O'Quinn) to the Wall.

The most unlikely hero of last night's highly successful naval air strike was Lieutenant Harmon Rabb, Jr., who saved Captain Thomas Boone's life when he safely landed this damaged Tomcat onto the deck of the Seahawk.

One of his most memorable moments was, in his zealous prosecution of a Navy SEAL Chief Petty Officer, he fired an automatic weapon into the courtroom ceiling.

[18] Other notable cases Rabb was involved in include going undercover as a Force Recon Gunnery Sergeant,[19] and investigating whether the actions of Navy SEAL Lieutenant Curtis Rivers (Montel Williams) warrants the Medal of Honor.

[20] After a few years as a Judge Advocate, he had laser surgery to correct what was misdiagnosed as night blindness (actually blurred vision as a result of retinal scarring caused by service action[21]) and resumed his career as a naval aviator, flying F-14s off the USS Patrick Henry (CVN-74) as a member of VF-218 "Raptors".

[25] In the season 8 episodes "Ice Queen" and "Meltdown"—the backdoor pilot for NCIS—Rabb is accused of killing Lieutenant Loren Singer (Nanci Chambers).

At one point, after being denied leave by his commanding officer, Rear Admiral Chegwidden, to rescue Mac, Rabb resigned his commission from the Navy.

[30] In the final episode, Harm and Mac decided to get married; also, each was offered a career promotion, but to different locations; Harm was offered the position of Force Judge Advocate at Naval Forces Europe and to be stationed in London, while Mac was to lead the Joint Legal Services Center Southwest out of Naval Base San Diego.

[32][33] Harm appears in the final two episodes of the tenth season of NCIS: Los Angeles as the executive officer (XO) of the aircraft carrier, USS Allegiance (CVN-84).

[2] Harm and Mac then met in person in the season 11 premiere, where they shared an embrace and later renewed discussion of their relationship, once again without reaching any conclusions.

[48] Rabb received his first Distinguished Flying Cross at the start of the second season in a ceremony at the White House Rose Garden by President Bill Clinton for saving the injured CAG, Captain Thomas Boone (Terry O'Quinn), of the USS Seahawk after the modified F-14 Tomcat they were flying was damaged by flak during an ATARS run prior to an alpha strike in the pilot episode.

Creator Donald P. Bellisario wanted an actor for the part of Harmon Rabb similar in the vein to that of Tom Selleck and Scott Bakula (which he had a hand in casting for Magnum, P.I.

[57] For the surname he got the inspiration from Princeton University history professor Theodore Rabb, whom he had met on a cruise in the Mediterranean Sea while he wrote the pilot.

[64][65][66] Entertainment Weekly elaborated further on it: in each case it is a "hunky loner", partnered with "attractive women with whom they have a charged yet ultimately platonic relationship", each working for the U.S. Government and based in the DC metropolitan area, with seemingly "unlimited travel budgets": with the key thematic difference being that in JAG with its "red-white-and-blue patriotism" the "U.S. military is seen as a force fighting for good around the world" while the other series displays "antiauthoritarian cynicism" towards ditto.

[67] Time described the character of Rabb in 2001 as a "buff-bodied flying ace who packed a gun, a straight-arrow defense lawyer without the moral ambiguity of his counterparts on The Practice".