Gabby, Pandy Paws, her Gabby cats, and her dollhouse go on a road trip with her grandmother Gigi to visit her home for a special project. In
Cat Francisco, CatRat accidentally unlatches the dollhouse from the van, causing it to roll into a store where Vera, a cat lady, buys it and drives home. Vera then splits the Gabby cats up. CatRat finds a plush cat named Chumsley in a drawer. Gabby, determined to save her dollhouse, shrinks along with Pandy and is taken to Vera's home, where the dollhouse is. Gabby learns the Gabby cats are missing but meets Chumsley at Cakey's kitchen, while ordering CatRat to stay. Chumsley offers to help. Gabby and Pandy find MerCat in Vera's aquarium and jump in, turning into mermaids. They free MerCat, traveling in a bubble, and find the Gabby cats in a bag. Vera opens the door, causing them to fly outside and fall into a bush. They meet kitty gnomes who take them to the Kitty Fairy, their queen. At the kitty gnomes' hideout, they trick the gnomes into playing hide and seek while building a bird-like vehicle to escape. The Kitty Fairy gives up her queen title and returns to the dollhouse with MerCat. Meanwhile, Gabby and Pandy try to free the Gabby cats as Vera is distracted by Kitty Rangers. Gabby rescues the cats and they return to the dollhouse, where Chumsley shares how Vera once played with him but grew up and left him in her drawer. Gabby, Pandy, and the Gabby cats are cast out, and Chumsley seals the windows, claiming ownership of the dollhouse. Pandy goes to get Gigi. CatRat unlocks the door and the team enters the dollhouse to stop Chumsley. Gabby nearly pinches her cat ears, but Chumsley steals them, corrupting the dollhouse. Gabby tearfully tells Baby Box she's scared of growing up, and Baby Box comforts her, giving her back her cat ears. Carlita returns with a smaller Gigi. Gabby reunites with Gigi and shares what happened. Chumsley makes a cake with a bunch of magic, accidentally creating a portal. Gabby becomes big again to get Vera, then they both turn small and meet Gigi and the Gabby cats. They find the portal in Cakey's kitchen, which sucks Gabby, Vera, Cakey, and Chumsley into a world of sweets. Gabby, Vera, and Cakey see Chumsley's paw prints and ride animal-shaped cookies to catch up.
Gummy worms erupt from the candy grounds, carrying them away, and Chumsley escapes. The ground collapses, and they fall into a river, floating on a donut. As Vera talks about growing up, Cookie Bobby, a friendly cookie monster, throws them to safety, while Chumsley crosses a sweets-made rickety bridge. Before Vera can reconcile with Chumsley, he destroys the bridge. The magic from the dollhouse begins to fade, causing the world to start collapsing. Vera and Chumsley save each other and reconcile, while everyone manages to return to the dollhouse. Its magic is restored, and a balloon shaped like a cat inflates from the dollhouse, lifting it as it flies over Cat Francisco. Back at Gigi's home, Gabby helps build the special project Gigi has been working on: a dog-themed dollhouse for Gabby's sister. ==Cast==