The pets suspect a Siamese cat visiting the day camp is preying on Mrs. Twombly. Meanwhile, Blythe encourages the Biskit twins to join their mathlete team after she overhears them using narratives of their daily life to solve complex math equations.

Russell, Zoe, and Vinnie, along with Buttercream, try to retrieve a recipe stolen from Blythe by the Biskits, who plan to use it for a baking competition hosted at Blythe's school. All the while, Vinnie has a vision of cakes occupying the world.

An endangered specimen of cobra escapes from within a pet carrier of Fisher Biskit, after finding a potential buyer for it. Meanwhile, after three straight days of rain, the pets go on a walk with Blythe to their public park. Sunil breaks away from the group, and finds himself among a group of tribal raccoons, as well as a pigeon who can understand them. There, they find the escaped cobra, and Sunil saves them after confronting it using his primal instincts. They celebrate, and the raccoons force Sunil to stay with them indefinitely as their king.

When Blythe fills in for Zoe's owners and accompanies her to a dog show in Paris, they suddenly find themselves smitten; Blythe with the city and Zoe with a mime artist dog named Philippe.

At the Pet Expo, the Biskits sabotage Blythe at every turn, fueling superstitions over her entry. At the end, the Pets and Blythe are able to recover her stuff and exposes the Biskits' sabotage. The Biskits' butler confesses that they made him take part of their scheme. They fired their butler. The butler became a photographer. The Biskits are humiliated and expose for their crime. Blythe won the International Pet Fashion Expo. Pets got their faces at the magazine.