After his partner is murdered, veteran plain clothes Detective T.J. Hooker (William Shatner) reverts back to his former role as Sergeant, and returns to the beat to rid the streets of the type of scum that was responsible for his partner's death.

Back in uniform, Hooker is assigned to train the academy recruits, and is partnered with brash, sometimes hot-headed young rookie Vince Romano (Adrian Zmed). With Romano much his junior, Hooker acts as his trainer and mentor on both a professional and social level.

Hooker's tough, no-nonsense ways see's him often clashing with station Captain Sheridan (Richard Herd), but he always gets the job done and is highly respected as a result.