The Little Shop of Horrors (1960)
Roger Corman's 1960 horror comedy starring Jonathan Haze and Jack Nicholson. The film's cult following would inspire the 1982 off-Broadway musical, which was in turn adapted into the 1986 Little Shop of Horrors feature starring Rick Moranis.
Clumsy Seymour (Haze) works in a skid row florist shop and is in love with his co-worker, Audrey (Jackie Joseph). He creates a new plant that not only talks but cannot survive without human flesh and blood.