Being also the unwilling love interest of Teresa Del Taco, a lesbian taco, Brenda is the love interest for two characters in the same film.
In a supermarket called "Shopwell's", the food who live there see the humans as gods who reside in their homes nicknamed "The Great Beyond". Among these is a sausage named Frank, packed in with the bisexual Carl and deformed Barry and Frank is infatuated with Brenda, a hot dog bun, whose pack is near his.
One day, Frank and Brenda's packs are chosen by a woman named Camille Toh, but a paranoid honey mustard jar who has seen "The Great Beyond" warns Frank and Brenda, telling them to visit a bottle of liquor named Firewater before attempting suicide by jumping off the cart.
Then, Frank leaps out of his package to save the honey mustard and Brenda comes out of hers to save a slipping Frank, but Frank loses his grip on the honey mustard who shatters on the ground below.
His death causes a collision that leads to Frank, Brenda, a lavash named Vash, a bagel named Sammy Bagel Jr. and an aggressive Douche to fall out of Camille's cart.
The Douche's nozzle badly dents and he blames Frank before he is swept away by Darren, the store's manager.
Escaping the trash, the disillusioned Douche swears revenge and consumes the contents of a wounded juice box, giving him strength.
With the groceries purchased albeit, Frank, Brenda, and their new friends decide to journey back to their respective aisles, but Frank heeds Honey Mustard's warning and leads them to the liquor aisle to find Firewater.
Frank is separated from his gang which is led into a liquor bar by a bottle of Tequila that is secretly working for the Douche. There they befriend a lesbian taco named Teresa who takes a lustful passion for Brenda and manage to escape before Douche arrives.
Frank finds Firewater and the 'Non-Perishables': Mr. Grits and Twink who have seen humans serving food meals. Frank vows to reveal the truth, but Firewater tells him to head to the aisle behind the freezer to find proof.
Meanwhile, Barry, Carl, and the rest of the groceries realize their fate when they terrifyingly see Camille skinning a potato and broiling him as she begins cooking unaware. Carl is halved mid-escape, forcing Barry to stow away in a drug addict's shopping bag.
After taking bath salts, the druggie sees Barry and his groceries alive and after freaking out, he is ordered by Barry to return them to Shopwell's. The man agrees, but passes out. The man wakes up sober the next morning and first opens a bag of chips before attempting to cook Barry, clumsily decapitating himself in an mishap.
Frank reunites with his friends, but when he reveals that he deliberately led them to Firewater and reveals his intentions to travel beyond the freezer to discover the truth, causing Brenda to question his motives and ultimately desert him. Frank ventures beyond the freezer alone, and after discovering a cookbook, finally discovers the truth. He reveals the book to the entire store, but feeling purposeless without their beliefs and believing the humans are immortal, everyone ignores the truth. Barry's group enter Shopwell's through a vent and after reuniting with Frank, reveals that the humans can be killed by revealing the druggie's decapitated head.
Shooting the humans with toothpicks laced with bath salts and causing them to see food for what they are, Frank saves Brenda from getting taken and gives a more inspiring speech to help convince the other food items to stand against the humans and kill them off one-by-one.
Meanwhile, a revenge-seeking Douche takes control of Darren armed with a gun and attempts to kill Frank, but Brenda interferes and with the help of the other foods, Darren and Douche are sent flying out the store roof by a propane tank propelled cart which explodes, killing them both.
The delicacies celebrate their newfound freedom with a "food orgy", and Frank and Brenda finally do have sex in which the two have such great pleasure. However, Brenda also has sex with Teresa unwillingly, as Teresa performs oral sex upon Brenda's anus and crotch. When Brenda finally realizes that Teresa took over Frank's place, she stops enjoying it and tries to force Teresa off of her, but to no avail.
Then, Firewater informs them that they are merely cartoon characters being manipulated by animators and voiced by celebrities. Gum, a Stephen Hawking-esque wad, builds a portal to the real world and the group of food enters it to take revenge on their creators.