Garfield is dreaming about being a submarine captain with Pooky as his commanding officer. The dream continues even after the alarm clock wakes him, and he joyfully fires a torpedo that smashes the clock, a small victory that kicks off a wild morning of pretend adventures.
Morning brings a playful succession of fantasies: a cowboy greeting for Odie and a magician-themed breakfast that hinges on waking Jon Arbuckle. Odie joins the magic, and the trio dives into a game where the line between dream and reality grows blurrier by the minute.
To test whether these fantasies are truly harmless, they leap into a jet-pilot fantasy aboard a plane with faulty engines. Jon’s timely rescue from a near-fall confirms their theory, and they promptly retreat into the refrigerator, ready to slip into another dream.
In the new daydream, Garfield becomes Lance Sterling, a stylish fusion of James Bond and Indiana Jones, while Slobber Job acts as his loyal bodyguard. The duo heads to Istanbul and encounters the villainous Fat Guy and his steadfast lieutenant, Rameet. They’ve been sent to locate the Banana of Bombay, the first banana famous for a classic banana-peel gag, but it vanished years ago and the map to it was split in half inside a holy ankh. Fat Guy explains he intends to sell the Banana to the highest bidder. Lance Sterling mocks Fat Guy before agreeing to join halves of the ankh, but he secretly steals Fat Guy’s half and escapes with Slobber Job. When Fat Guy’s henchmen close in, a woman named Nadia distracts them so the heroes can slip away. She claims their employers sent her to protect them, but Lance Sterling tells her they don’t need the help and tells her to leave.
The pair weld the two halves of the holy ankh to a supercomputer and uncover a twist: the map does not point to the Banana of Bombay after all, but to a clue revealing the banana’s true location. Their quest takes them to Paris, where a humorous misunderstanding with a French waiter leads to a reunion with Nadia, who warns that Fat Guy and Rameet are on their trail. When Slobber Job tries to challenge Rameet, he is knocked toward an awning and uncovers another map that points toward the Banana.
Their journey next brings them to the Amazon rainforest, where they uncover a temple holding the Banana of Bombay. The precious fruit rests on a pedestal in the middle of a pool of lava, but Nadia swoops in and takes the Banana for Moldavia, explaining that her country, though poor, is banking on tourism and needs the Banana to set up a fruit stand. Fat Guy and Rameet seize the Banana again and trap Lance Sterling, Nadia, and Slobber Job on the pedestal. Rameet tumbles into the lava, Slobber Job manages to pull everyone to safety, and a troupe of monkeys swipes the Banana from Fat Guy. Lance Sterling and Slobber Job manage to reclaim it and sprint away, pursued by Fat Guy, Nadia, and the mischievous monkeys. Cornered at a cliff, they use the Banana to slip all their pursuers into a river; Rameet survives the lava fall, and the heroes are forced to leap off the edge.
Back in the real world, Garfield and Odie tumble out of the refrigerator. When Jon asks Garfield if he had another fantasy, Garfield says it was his last one—then slips into another dream that mirrors Casablanca, leaving the audience in a lingering, playful sense of wonder.
