Mac's ""little sister"" unexpectantly shows up at JAG headquarters, declaring that she's run away from her abusive stepfather. While she investigates whether Chloe has been abused, Mac has her hands full keeping her from turning the office upside down, then learns that her real father is still alive serving on a ship in the Navy. Despite the cost, Mac convinces the Admiral to allow the two to talk to each other via satellite video-conferencing.

Meanwhile, Harm spends the evening interrogating a beautiful Navy doctor arrested for DWI after she lost control of her vehicle on icy roads and ran over a Nativity scene. Harm agrees to defend her when he learns that just before the accident and before she took the breathalyzer test, she had drank some liquid cold medicine (which contains 25% alcohol)

Adm. Chegwidden's attempts to fly to Italy to spend Christmas with his daughter, however, with the Washington, DC area mired in snow, most of the flights out have been cancelled.

With Harm's eyesight fixed, Harm decides to go ahead and submit a request to be transferred to a fighter squadron. When Lt.Cmdr Parker finds his written request, she is upset at the prospect of Harm being gone for months at a time.

Afterwards, Harm goes over to Mac's apartment who has Chloe spending the night with Mac before she is reunited with her real father. Harm informs Mac of the eye surgery and his plans. Mac is equally upset at the prospect of losing Harm. Mic shows up at Mac's apartment after Harm leaves attempting to court Mac's feelings. After Mic leaves, Chloe tells Mac that Brumby and Harm have a crush on her and begins teasing Mac: ""Harm & Mac, sitting in a tree, k-i-s-s-i-n-g.""

Admiral Chegwidden passes Harm's request to be transferred onto the SecNav. Not willing to do any favors for Harm, the SecNav is reluctant to intervene.

When a Navy research project involving psychic phenomena goes awry and results in the death of one of its research subjects, Harm defends the admiral in charge of the project. As Mac prosecutes, she steadfastly proves that the admiral's ESP theories are wrong. But when her friend Chloe disappears and Mac experiences a vision that could save her life, she begins to have second thoughts about the paranormal.

Mac becomes upset when Harm tells her at the last minute that he will not be attending her rehearsal duty in order to complete his 6-month required carrier landing qualifications. He assures her that he will be back in time for the wedding. At the church, Chloe is still wary of being friends of Mic. On board the USS Patrick Henry, Harm learns that the LSO who will be grading him thinks of him only as a "land-based Washington weenie." His fears that he won't be graded fairly are realized when he is ordered to land after his first attempt is waved off. After convincing the LSO that they were flying they way that the LSO taught them, he allows Harm to try again. After passing, he then completes his required night traps and requests to head back to Andrews AFB. With an approaching storm, all air operations are suspended, but is assured that he & Skates can be on the first Tomcat, once its forecasted to be safe. With a break in the storm, he & Skates are allowed to go.

Harm's chance of being rescued from the Atlantic Ocean hinges on Mac's psychic ability (first seen in Season Five's "Psychic Warrior"). However, Mac is trying to cope with her conflicting emotions for both Harm & Mic. On the edge of going unconscious from severe hypothermia, Harm's fires several warning shots which attracts the rescue helicopter. Back onboard the USS Patrick Henry, Harm's vital signs start to fade out, but Skates words help him pull through. Transferred to Bethesda Hospital, Renee learns that Harm has partial amnesia and doesn't remember them being a couple over the past year. Mac's indecision about the wedding drives Brumby back to Australia. When Harm tells Mac on the phone to come to his place so that she doesn't have to be alone, she arrives only to learn that Renee has beaten her to Harm's place with the news that her father has died. Mac ends up in the rain with no one around.

Unwilling to face her pain over Mic & Harm, Mac is granted temporary assignment on the carrier USS Guadalcanal (along with Gunny) when the staff JAG there disappears.

Harm returns to active duty after returning from Renee's father funeral.

""AUGUST 7, 2001""

Following the transfer of a U.S. Marine accused of rape from the local Indonesian police to his CO at the Indonesian consulate, the consulate comes under siege by angry, armed locals.

When the commander of the Marine detachment is killed and his next-in-command is blinded during the surprise attack, Mac realizes that she is next in command and must organize the emergency evacuation of the consulate under fire.

Back at JAG, Harm defends a SEAL accused of killing a person onboard a flight that Harriet was a passenger.

Un natale difficile per Rebb che crede gli sia stata rubata la seconda Corvette e deve controllare in custodia una sottufficiale in gamba ma molto propensa alla piccola delinquenza. Tutto però si risolve, Harm e Mac si baciano sotto il vischio e al muro dei caduti incontra il suo fratello russo appena liberato da un amico della CIA.