Plot
Gracie, a friendly and brave timber wolf, lives with her pack at Colepepper Zoo, a massive animal theme park in western Canada. The pack’s paranoid elder, Gramma Abigale, trains them for any upcoming “disasters” and warns them never to trust the other animals.
One evening, as the zoo closes for the day, the pack witnesses a new animal being transferred to an enclosure. That night, a meteor crashes into the zoo, landing at the Kuddle Korner petting zoo, where a white rabbit eats it and becomes infected with a virus.
Gracie escapes her damaged enclosure to investigate the crash and encounters the rabbit, which is incubating in a giant pod. Suddenly, a zombie arm emerges from the pod and attacks her. She narrowly escapes, only to come face to face with the new animal, a gruff mountain lion named Dan, who instinctively attacks her. Both Gracie and Dan are tranquilized by an oblivious zookeeper, who places them in the veterinary station for the night.
Meanwhile, the rabbit emerges from the pod as a “Gum-Beast,” a zombified mutant with gelatinous skin. The rabbit, dubbed "Bunny Zero," spreads its infection across the zoo. Gracie, Dan, and four other animals - Xavier, a factitious red ruffed lemur; Felix, an egotistical proboscis monkey; Frida, a feisty capybara; and Ash, a sarcastic ostrich - escape being infected. They are attacked by Fred, an infected gorilla and Felix's abandoned partner, prompting them to split up and flee into the utility tunnels.
Gracie decides to head back to her enclosure and forces Dan to protect her on the way in exchange for the zoo card key, and they start their adventure to find the pack. Along the way, they meet Poot, an uninfected baby pygmy hippopotamus, who joins them on their journey. They arrive at the enclosure to find that the rest of the pack has already been turned. Meanwhile, the others find themselves in the gift shop, where they agree to stay for the night. Nevertheless, tensions rise within the group, which leads to a brawl that results in them accidentally powering on the entire zoo. As the Gum-Beasts attack, Felix abandons his group to find the card key, while Gracie, Dan, and Poot are attacked by Fred, who merges with an infected giraffe into a monster that infects Dan. The Gum-Beast Dan attacks Gracie until he is seemingly cured by being submerged in a security office sink filled with soap and water. Afterward, Dan leaves with the card key, coldly rejecting Gracie's idea to team up with the others.
At the gift shop, Gracie and Poot reunite with Ash, Frida, and Xavier to cure the Gum-Beasts, while Felix steals the key from Dan. Felix is attacked by a swarm of infected tree frogs, only for Dan to rescue him to reclaim the key. Felix successfully appeals to Dan for the card key, but is infected by the tree frogs before he can even use it. Meanwhile, Gracie and the others plan to cure the Gum-Beasts by luring them into Dan's enclosure and flooding it with soap and water. Dan returns to help the group, and the plan seemingly succeeds. However, the Gum-Beasts instead merge into a gigantic amalgam, which absorbs everyone but Gracie and Dan, who flee into the gift shop, shortly before the amalgam destroys it.
Dan and Gracie are attacked by the infected Poot, who accidentally activates a snow globe with a built-in music box and returns to normal. Gracie recognizes the melody from the music box as the Zoo's theme song, which plays at the clock tower every 7 o'clock. She recalls that the same song was played on the radio when Dan was cured. Realizing that the song itself is the cure, she decides to activate the clock tower.
After the amalgam absorbs Dan, Gracie rushes to the clock tower while Poot distracts the amalgam. The Gum-Beast Felix tries to ambush Gracie, but she successfully activates the clock tower. The music from the song destroys the amalgam and restores the other animals to their normal state.
In the aftermath, Fred forgives Felix for abandoning him, Ash and Xavier become best friends, and Abigale, along with the rest of the pack, begins to trust the other animals. Dan leaves the zoo for the wild, but gives Gracie the key in case she decides to join him if she gets sick of living in the zoo.
