Street gang member Jeff (Adam Baldwin) leaves the organization, seeking out a quieter existence. Meanwhile, gang leader Cinco (Danny De La Paz) and his minions have taken over the local high school, dispensing drugs with impunity. When Cinco is arrested, a rumor spreads that he's been sold out by Jeff. In the ensuing hostilities, Jeff's girlfriend (Deborah Foreman) is beaten and bloodied. A showdown is inevitable, and, per the film's title, it takes place just after the last school bell has rung. Filmed in 1984, 3:15 - The Moment of Truth wasn't released until 1986.
by Hal Erickson synopsis