Novelty of a gang swearing a blood oath to destroy a precinct station and all inside is sufficiently compelling for the gory-minded to assure acceptance.
Gang is motivated by a man who kills one of their members for the murder of his small daughter and takes refuge in the Los Angeles station so distraught he cannot explain. Assault closely follows his arrival, and it’s a war.
Precinct station is within hours of closing to move to new quarters, which explains why only a single cop and a policewoman remains to hold down the fort, abetted by two prisoners who are temporarily incarcerated on their way to Death Row in Salinas.
John Carpenter’s direction of his screenplay, after a pokey opening half, is responsible for realistic movement.