A downtrodden shop assistant working for an overbearing florist secretly creates an entirely new species of plant. However, he discovers it needs to feed on human flesh to survive and is driven to commit murder to keep it growing. Roger Corman's horror comedy, starring Jonathan Haze and Dick Miller, featuring an early screen appearance by Jack Nicholson.

Seymour works in a skid row florist shop and is in love with his beautiful co-worker, Audrey. He creates a new plant that not only talks but cannot survive without human flesh and blood.