The June 1962 Alcatraz escape was a prison break from Alcatraz Federal Penitentiary, a maximum-security facility located on Alcatraz Island in San Francisco Bay.Late on the night of June 11 or early morning of June 12, inmates Clarence Anglin, John Anglin, and Frank Morris tucked papier-mâché heads resembling their own likenesses into their beds, broke out of the main prison building via an unused utility corridor, and departed the island aboard an improvised inflatable raft to an uncertain fate. A fourth conspirator, Allen West, failed in his escape attempt and remained on the island.

Hundreds of leads were pursued by the Federal Bureau of Investigation (FBI) and local law enforcement officials in the ensuing years, but no conclusive evidence has ever surfaced favoring the success or failure of the attempt. Numerous theories of widely varying plausibility have been proposed by authorities, reporters, family members, and amateur enthusiasts. In 1979 the FBI officially concluded, on the basis of circumstantial evidence and a preponderance of expert opinion, that the men drowned in the frigid waters of San Francisco Bay before reaching the mainland. The U.S. Marshals Service case file remains open and active, however, and Morris and the Anglin brothers remain on its wanted list.New circumstantial and material evidence has continued to surface, stoking new debates on whether the inmates managed to survive.