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.

Nerdy Walter Paisley, a maladroit busboy at a beatnik café who doesn't fit in with the cool scene around him, attempts to woo his beautiful co-worker, Carla, by making a bust of her. When his klutziness results in the death of his landlady's cat, he panics and hides its body under a layer of plaster. But when Carla and her friends enthuse over the resulting artwork, Walter decides to create some bigger and more elaborate pieces using the same artistic process.

Myrt has a show chock full of talented performers that deserves to be on Broadway, but can't raise the necessary money. Jackson, a lecherous "producer", provides the money in order to get his hands on the show's pretty young star, Marge. Myrt teams up with Marge's boyfriend to try to thwart the randy producer and get the show to Broadway.