Hondo and his team go after a gang of jewel thieves who make their getaways under water.

Following a training exercise with S.W.A.T. officers from another division, Hondo and Street find the dead body of officer Frank Crane with the words ""Kill S.W.A.T."" pinned to his chest. The murder of Crane is the forerunner of a series of attempts to wipe out S.W.A.T. by brothers Mike and Simon Bishop and their fanatic sister-in-law, Joanna, who is convinced that the death of her husband was the result of S.W.A.T. ""brutality.""

Two officers go undercover to catch drug dealers.

Mel Lang and Ralph Costa have served sentences in prison after being framed by one Carl Rigby and arrested by Hondo Harrelson. When S.W.A.T. is called upon to assist police in evicting heavily armed brothers Will and Johnny Brewer from a home taken over by Rigby, Lang and Costa plan to execute Hondo and Rigby and create evidence pointing to the Brewer Brothers.

Runaway teenager Kathy Benson, seeking shelter in the warehouse, calls police when several men break in. Before fleeing the scene, Kathy gets a clear look at the leader, Gregg Colby, a prominent citizen and former U.S. Senator, attempting to solve his money problems by stealing from his own warehouse, collecting the insurance, and later selling his own ""stolen"" merchandise. He pretends to offer assistance to police investigating the case so that he can silence the only eyewitness, Kathy.

Radio repairman Paul Julian has patched in on the S.W.A.T. radio band so he can show up at a scene of police action, where he can observe and judge each case from a concealed position. when Julian decides to punish two disarmed gunmen who have been talked into surrendering by Lt. Hondo Harrelson, S.W.A.T. is suspected of causing the senseless killings.

Howard Wilson is jailed and his partners, Mike Simon and Frank Peterson, escape before S.W.A.T. moves in to combat a race track heist involving a female hostage. Wilson is on the brink of revealing the names of his partners when a high-powered attorney, Jason Bridges, assures him that Simon and Peterson are planning to free him at all costs--even if the price involves the lives of court personnel when Wilson goes to trial.

Hondo and a convicted dope dealer are stranded in rough terrain when syndicate thugs who want to keep him from testifying sabotage their helicopter.

Hondo and his team are assigned to handle security for a demagogic former general who now leads a racist paramilitary group.

D.A. Ainsely Stevens holds secret information which could convict two syndicate chieftains of capital crimes. Because Stevens insists on saying nothing until the grand jury convenes, and because police believe the mob has put out a ""major contract"" on Stevens, S.W.A.T. is assigned to guard him. But enforcer Mario Rosetti plans to abduct the prosecutor's daughter, Tory, and keep the girl until the father cracks. Oblivious to the danger, Tory is out for kicks as police and crooks try to track her down.

A man steals a tugboat laden with explosives and threatens to blow up a famous marine biologist unless he is given a million dollars.

Marco, an arsonist-killer posing as a fireman, engineers a fire during Southern California's dry season in the area's most affluent neighborhood. While looting the evacuated home of a wealthy couple, one of Marco's men kills a fireman. When S.W.A.T. is called in to locate a possible sniper, T.J. McCabe is shot and Marco escapes with a truckload of loot.

Millionairess Doris Bristol has brought gems into the hospital where she is undergoing cosmetic surgery. Her bodyguard, John DeLeon, is slain after he spots criminal Frank Malloy posing as a dying patient (part of a plan where a woman doctor and he plot to steal the jewels from the socialite). Hondo and his men, who are at the hospital putting together a Christmas party in the children's ward, find themselves on duty when the discovery of DeLeon's body leaves Mrs. Bristol unprotected and in apparent jeopardy.

Syndicate hit men stalk an undercover officer, who plans to testify against the mob.

The SWAT team protects a key government witness against an organized crime boss.

Hondo Harrelson and his team are called upon to investigate robbery-homicides in which powerful drills and cutting equipment have been stolen. Meanwhile, Dom Luca is dating a student, Sharon Merlingdale, who is being carefully watched by Mark Worth, one of the killer thieves. The more Sharon sees Dom Luca, the more convinced North becomes that the girl must be eliminated.

Bud Haskins, disowned after marrying a girl whom his father, John Haskins, disapproved, decides to help three ""professionals"" crack open the safe in the elder Haskins' warehouse. Bud is unaware that the thieves are actually after a huge arsenal of sophisticated, unmarked weapons that have been secretly imported for sale. Bud is slain after helping the criminals burglarize the warehouse. Although S.W.A.T. is assigned to investigate the burglary-murder, John Haskins recruits members of a tough Eastern mob to find the killers of his son.

Lt. Eddie Chew is assigned to aid Lt. Hondo Harrelson when an elderly shop owner is fatally beaten by an illegal Chinese alien working as a shakedown man for Albert Parker, the Caucasian leader of what appears to be an all-Oriental crime syndicate, a deadly drug and protection ring. Hondo begins to doubt Chew's integrity when it becomes obvious that Chinatown criminals are being given secrets of his investigation.

Clues to the perpetrators of a series of rapes are a religious medal and a Biblical quotation overheard by one of the victims.

A group of militants take over a radio station and demand that their jailed leader be released or they'll blow it up.

A mentally unbalanced veteran touring a movie studio suddenly thinks he is back fighting in Vietnam.

As Lt. Harrelson lies in a hospital bed, severely wounded, the other members of the team reminisce about their best moments together in clips from previous episodes.

Luca is charged with manslaughter after he is forced to kill a man who was holding his own wife hostage at gunpoint.