Falcon is a raccoon who thrives on the streets by scavenging food from various bins and carts, all to support his friends. He was raised by a pigeon named Rico, but for the street cred, Falcon prefers to think of himself as having been nurtured by a falcon. Interestingly enough, his real name is Maurice, yet he takes on the more heroic name, Falcon, which suits his adventurous spirit.
One day, he encounters a badger named Hans who proposes a daring train robbery. Hans plans to steal food from a train, hoping to procure enough for a lavish Christmas feast for Falcon and his eclectic group of friends. Accepting this audacious offer, Falcon deftly hacks into the train’s systems, granting Hans remote control. Hans then broadcasts a menacing pre-recorded message demanding the passengers vacate the train, leaving behind only the animals in the last carriage.
In this carriage, a vibrant assembly of pets resides: Anna the anaconda, belonging to a rapper, police dog Rex, spotted cat Maggie, social media influencer animals Candy and Randy, a couple of rabbits named Jimi and Janis, a duo of parrots Croquette and Coco, a haughty greyhound Victor, a mourning hamster, a duck, a turtle named Leo, and a clownfish named Momo.
As the scenes unfold, it soon becomes clear that Hans has a vendetta against Rex. Many years ago, Rex had thwarted Hans's gang, which led to Hans being sent to the pound. Worrying about the train’s imminent crash into another city, Maggie uncovers a critical detail about their situation: they face an imminent disaster if they pass over a certain bridge that cannot support the train's weight. With a sense of urgency, she suggests that to prevent catastrophe, they must escape their carriage and uncouple the second-class carriages at the train's midpoint.
With great determination, Falcon manages to release most of the trapped animals, although a mishap occurs that leaves Momo, the clownfish, stranded in a toilet until Falcon can collect water for him. Meanwhile, the train barrels through the city, wreaking havoc as it attracts media attention. Two reporters, Cynthia and Michael, pursue the train, eager to capture any thrilling footage to boost their flagging ratings.
However, their excitement for potential chaos grows as internal damage mounts, including a kitchen fire caused by an exploding propane tank. Their ratings obsession leads them to exploit the worrying circumstances around a frantic Lisa, Maggie’s owner, convinced that uniting them will heighten viewer interest. Meanwhile, Rico and a trio of rats, whom Falcon affectionately calls his uncles, witness the unfolding drama on the news, prompting Rico to leap into action with the hope of intervening by jumping on a helicopter.
As the train reaches Devil's Bridge, both Falcon and Rex bravely work to uncouple the train carts, ensuring that Rex can leap to safety. Though the bridge ultimately collapses under the burden, the train shockingly continues onward, carrying dangling carriages. Falcon's deception and compromise come to light when Rex confronts him, revealing the troubles the prior heist initiated. Although originally in it for the food, Falcon must now address the chaos they have caused.
When Hans utilizes the train’s controls to send Falcon plummeting out of a cart, the animals feel a profound loss, but Falcon miraculously survives, landing on a branch that subsequently gives way. The chopper tracking the train receives further intel when the city’s rail switches are altered to redirect the train towards another calamity. Heart-to-heart dialogue aligns Falcon with Rico, who expresses pride in Falcon, pushing him to set things right.
Rex and Maggie manage to infiltrate the control room, but Hans intercepts them on a drone, leading to intense moments involving heroism and collaboration among the animals to steer the train and switch tracks. On the other hand, Cynthia and Michael’s unethical journalism threatens to expose their corruption when Lisa captures evidence of their deception.
After defeating Hans, Falcon hits the emergency brake, thereby halting the train and allowing the animals to flee safely. With Randy and Candy adopted by a compassionate fireman after their previous owners exploit their popularity, Falcon ultimately parts ways from his friends but retains a hopeful disposition. As Falcon embarks on a new journey to uncover food at the airport with Rico by his side, the story closes with a mid-credits scene featuring Falcon’s enthusiastic rat uncles awaiting his return back home, a testament to the enduring bonds formed throughout their challenging escapades.
