A supermarket called Shopwell’s is filled with anthropomorphic grocery items that worship the human shoppers as gods who take groceries to a utopia known as the “Great Beyond” when they are purchased. Among the groceries in the store is a sausage named Frank, who has dreams of living with his hot dog bun girlfriend, Brenda, in the Great Beyond, where they can finally consummate their relationship.
After Frank and Brenda’s packages are chosen by a woman named Camille Toh to leave Shopwell’s, a returned jar of Bickle’s honey mustard tries to warn the groceries that the Great Beyond is a lie; nobody listens except for Frank. Honey Mustard calls on Frank to seek out a bottle of liquor named Firewater, and then throws himself to his death. This creates an accidental cart collision that causes Frank, Brenda, and several groceries to fall out, including a douche who gets his nozzle bent, and plots revenge against Frank and Brenda.
Seeking to verify Honey Mustard’s warning, Frank leads Brenda, a lavash named Kareem Abdul Lavash, and a bagel named Sammy Bagel Jr. to the store’s liquor aisle under the guise of taking a shortcut to their proper aisles. There, he smokes weed and learns from Firewater that he and other non-perishable foods invented the story of the Great Beyond as a noble lie to assuage past foods’ fears of being eaten by shoppers. Frank, vowing to reveal the truth to the groceries, is encouraged to travel beyond the store’s freezer section to find proof. While waiting for Frank, Brenda and the others are led into the Mexican aisle by a bottle of Tequila, where they meet Teresa, a taco who falls in love with Brenda on sight.
Meanwhile at Camille’s house, Frank’s friends Carl and Barry are horrified as they witness the other purchased foods being cooked and eaten by Camille, shown from the foods’ perspective as a brutal murder. Carl and Barry attempt to escape out a window, but only Barry succeeds after Carl is sliced in half by Camille. Barry stumbles across a human druggie, who becomes able to communicate with his groceries after he injects himself with bath salts. After sobering up and attempting to cook Barry, the druggie is decapitated in a domestic accident.
After Frank separates from his friends, who disapprove of his skepticism of the Great Beyond, he discovers a cookbook behind the freezer section and reveals its contents to the rest of Shopwell’s groceries. Initially panicking, the groceries choose not to believe Frank out of fear of losing their sense of purpose, prompting Frank to lash out at them for their blind belief. Barry and other groceries from the druggie’s home return to the store with the druggie’s severed head, revealing that the humans can be killed. The groceries are able to drug the human shoppers and employees using toothpicks laced with bath salts. When the drugged humans begin attacking the groceries, Frank convinces everyone to listen to him and join the fight against the shoppers, and a store-wide battle ensues.
Douche, after absorbing the contents of liquor bottles, becomes a wild monster and takes control of Darren, the store manager, by inserting himself into Darren’s anus and yanking on his scrotum to puppeteer his actions. Once he and Darren catch Frank, Douche gets revenge by biting on Frank’s torso. Barry and the other foods launch a rocket at Douche and Darren made from propane tanks and a garbage bin used to dispose of expired foods. Brenda rescues Frank from Douche and Darren just as the rocket hits them, sending them both through the store’s ceiling and killing them in an explosion. With the battle over, the foods celebrate their victory in a massive orgy.
Afterwards, Frank, Brenda, Barry, Kareem, Sammy and Teresa meet with Firewater and Gum, a Stephen Hawking-esque wad of chewing gum, who have had a psychedelic experience and discovered that their world is not real, and they are merely cartoons voiced by famous actors in another dimension. Gum has constructed a portal to this dimension, and the groceries decide to travel there to meet their creators.