Ozzy the Beagle leads a bright life with the Martins—Susan, Ted, and their cheerful friend Paula—until a trip to Japan for a Comic Festival brings trouble. The family is thrilled about a vacation, but Ozzy cannot go due to a quarantine rule, so they search for a caregiver for their beloved dog. An online ad for a dog hotel called Blue Creek catches their attention, promising comfort while they’re away.
At the hotel, the Martins meet the owner, Mr. Robbins, who offers a tour and shows off a spa-like setup with saunas and a massage room. Susan and Ted are impressed and decide to leave Ozzy in Blue Creek for their trip. Yet the place hides a dark secret: behind the inviting façade, the hotel is a front for something sinister. Ozzy and several other dogs are secretly loaded into a truck by Robbins and his assistant Dominic, destined for a grim fate.
The truck stops, and the dogs are ordered out by a fearsome Great Dane chief guard named Decker. Ozzy discovers that Blue Creek is a prison for dogs, not a hotel, and a stern St. Bernard warden named Grunt ignores Ozzy’s pleas of innocence as he grabs his collar and assigns him the number 463. In a damp, crowded cell, Ozzy meets a short-sighted Dachshund named Fronky who explains that many dogs have waited for owners who never returned. Fronky reveals a plan to escape and invites Ozzy to join him.
Life in the prison begins with harsh routines. Decker assigns Ozzy to sorting colored toy saucers, but a mistake lands him in a washing machine as punishment. Meals are grim, and the dogs are not allowed to sit where they please. Chester, an older Fox Terrier, and Doc, a silent Old English Sheepdog, strike up conversations with Ozzy. Chester, who has a hurt leg, shares that he was abandoned by his own people, and he hints that hope of a reunion may be faint.
A new voice arrives: a small dog named Radar alerts the inmates that it is day 6, and the notorious prisoner Vito—a tiny black-and-white Chihuahua—will soon be released from the hole. Vito makes his presence felt with a chilling display of power, pinning Ozzy before Decker warns them that trouble lies ahead. Ozzy remains focused on his family, even as the grim reality of the prison presses in.
When Fronky disappears one morning, Ozzy learns that he has been forcibly removed after another failed escape attempt. Fronky, never giving up, makes his own bold efforts to slip past the warden by climbing roofs, crawling through air vents, and even hang gliding over walls—only to end up in Grunt’s office again and again. Fronky eventually shows that he can guide others and even helps a blind man named Bob along safe paths as a true guide dog.
A turning point comes when Radar announces a meet-up with Vito, who tests Ozzy’s speed by pitting him against a runner named Flash. Ozzy wins in a late surge, and Vito offers him a high-stakes role as his runner to beat the guards in a grand race. Ozzy asks for time to think—Vito grants him 24 hours.
Friends warn Ozzy that racing for Vito will only deepen the prison’s cruelty, and they fear the consequences. The plan to escape grows more urgent as days drift by without any message from Ozzy’s family. Then the Martins return home, but the truth unspooled by Mr. Robbins breaks their hearts: Ozzy is said to be dead, and Paula weeps for a furrowed loss.
Under pressure, Ozzy contemplates the race offer but remains determined to protect his friends. He rejects Vito’s deal and resists the guard’s coercion, choosing to stay loyal to those who have supported him. Yet the tension remains high. The dogs—Fronky, Chester, and Doc—stand by him, sharing the burden of the danger and the hard reality that escape is a double-edged weapon.
The escape plan intensifies. The quartet must reach the truck by hiding in boxes of toy saucers and navigating underground passages to the factory. They need the warden’s blueprint to map their way, so Fronky convinces Chester to help. They seize the moment when Grunt is away; in a tense raid of the warden’s office, Doc uncovers old photos of himself and his owner, Mike, evoking a promise Ozzy makes to reunite with him someday. The trio escapes through a window and lands in a bush, only to begin a dangerous chase to complete the plan.
Back at the prison, Vito and Grunt strike a preliminary deal: if Ozzy wins, the prisoners’ real food becomes available; if Ozzy loses, the inmates face night shifts and more cat food. The deal tightens the pressure, and even though Chester advises against it, the crew votes to escape and seize their freedom.
On race day, the track is taut with anticipation. Ozzy faces undefeated champion Jock and runs neck-and-neck with the guards. Just as the finish line looms, a blackout disrupts the race, and Ozzy vanishes from sight. Decker and the guards search in a panic, but Ozzy, Fronky, Chester, and Doc slip into the factory via an air vent and hide in crates bound for the truck. Robbins and Dominic eagerly drive away, unaware that the escapees have followed their own trail.
The truck halts, Decker reveals that Chester left an oil stain in Grant’s office to betray nothing, and the four dogs are captured and dragged back toward the warden’s office. In a bold move, Ozzy confronts Grunt with a defiant declaration that he is not 463 and not bowed to the warden’s lies. He reveals his true name and discloses the master plan behind the collars—the dogs have been robbed of their memories and identities until now. Ozzy and the others tear off their collars, reclaiming their memories and freeing the prisoners from the control that Grunt and Grant had wielded for so long.
With the truth exposed, the prison erupts in resistance. The dogs band together to fight the guards and reclaim their freedom. Robbins is captured, and Vito faces off against Grant in a dramatic confrontation that ends with Grant crashing onto a control button, opening the gate. The dogs sprint onto the street, leaping onto the truck to escape, while Vito settles unresolved business with Grant and Decker.
Back in the city, Ozzy reunites with Fronky and Doc and returns them to their rightful homes. Chester, left behind for a moment, is later found by Paula under the Martins’ table, alive and well. The Martins finally accept Chester into the family, and the dog’s status as a cherished companion is sealed.
In the closing moments, a reporter reveals that Mr. Robbins has been sentenced to twenty years for animal cruelty, and every dog affected by the ordeal is joyfully reunited with their families. Ozzy learns a valuable lesson: fear should not paralyze him, and he and his friends stand ready to defend their homes and each other. The neighborhood’s once-scared dogs and their owners live in renewed harmony, while the brave neighborhood dog who sparked the change—Ozzy—becomes a symbol of courage and resilience for all.
