Half-fact, half-fanciful and all riveting, this documentary is based on the memoirs of Robert Evans, the starlet-screwing, enemy-skewering Hollywood player who ran Paramount from 1966 to 1974 when the studio churned out such hits as Rosemary’s Baby, Love Story and The Godfather. Drug problems, losing wife Ali MacGraw to Steve McQueen and a connection to a murder case are all touched on, but since Evans narrates himself — in a voice that defies description — the spin is in. No matter. With clips, photo collages and footage of Evans at home in Beverly Hills, shot by the masterful John Bailey, this stuff is golden. Directors Brett Morgan and Nanette Burstein make sure the movie goes down like potato chips. It’s great fun and compulsively watchable. And don’t leave before Dustin Hoffman makes a hilarious appearance as the credits roll.