New York City Private detective John Shaft gets a pre-dawn phone call from a panicked friend, Cal Asby, but he arrives at Asby's funeral home just before the building blows up--killing Asby and starting an underworld war in Shaft's Big Score. Searching for Asby's killer, Shaft (Richard Roundtree) soon learns that Asby ran a gambling racket, doing business with Harlem gang lord Bumpy Jonas (Moses Gunn). Now the racket's cash is missing; rival gangs are battling for Asby's turf ... and only one man's bad enough to stop the violence--John Shaft!