Burger-Beard is a pirate/restaurant entrepreneur who is the main antagonist in The SpongeBob Movie: Sponge Out of Water.
Burger-Beard makes his first appearance at the beginning of the film, where he steals a magic book and defeats the skeleton pirate who guards it. Although the skeleton pirate defeats Burger-Beard in a fight and sends him flying back to his ship, he still remains victorious due to using the book as a shield.
He then starts to read a story to some talking seagulls. Burger-Beard seems to know all about SpongeBob and his friends and, from the book, he learns that everyone in Bikini Bottom is happy thanks to the Krabby Patty. Aware of the book's immense powers, and obsessed to have the same business as Krabs, Burger-Beard then rewrites the book, which makes the Krabby Patty secret formula instantly teleport on to his ship. Once he succeeded, he converts his ship into a food truck to sell Krabby Patties at a beach community named Salty Shoals. In doing so, Burger-Beard also sends Bikini Bottom into a post-apocalyptic state, forcing SpongeBob and Plankton to form an uneasy alliance to solve the mystery. Burger-Beard likely knows that his actions are bringing the destruction of protagonists' town, but he doesn't care.
When the heroes arrive at his food truck, he is busy cooking Krabby Patties. This angers Mr. Krabs, who then demands an explanation on how he stole the formula and built such a business. Confused by their presence, Burger-Beard checks his magic book and said that the book never foretold this. Knowing that SpongeBob and his friends would take back the recipe, he demonstrates his reality-warping power by writing in the magic book to make it say that SpongeBob and his friends are teleported away to Pelican Island, which is simply a rock full of pelican colonies.
However, using Squidward's ink and one of the ripped pages, SpongeBob and the others return to confront Burger-Beard as super-powered heroes with special powers - SpongeBob becomes The Invincibubble, Patrick becomes Mr. Superawesomeness, Squidward becomes Sour Note, Sandy becomes The Rodent, and Mr. Krabs becomes Sir Pinch-a-Lot. Upon re-encountering the confused Burger-Beard, Squidward, as Sour Note, uses his terrible clarinet playing to drive off all of the pirate's customers. Burger-Beard attempts to manipulate the story yet again, although Mr. Krabs, as Sir Pinch-a-Lot, uses his robotic claws to pin his arms to his ship while SpongeBob, as the Invincibubble, creates a bubble to float the book away. The heroes put their hands in the circle to celebrate their victory, and, needing one of his claws, Mr. Krabs takes one back, releasing one of Burger-Beard's hands, unintentionally allowing the pirate to free himself and drive off after the book, forcing the team to give chase.
Burger-Beard and the heroes enter a chaotic chase throughout the city, ultimately resulting in the book falling onto and getting burned to bits by Burger-Beard's stove. The team attempts to apprehend Burger-Beard, but he easily overpowers them. But when he is about to flee, Plankton, who'd seemingly been left on Pelican Island after hiding in SpongeBob's sock and hopping out, arrives to assist them, now as the muscle-bound hero Plank-Ton. After retrieving the formula, Plankton and SpongeBob work together to create one final attack that sends Burger-Beard all the way to Bikini Atoll.
It is completely unknown if Burger-Beard ever escaped from Bikini Atoll or not.