Caillou is outside playing with Gilbert and Grandpa is there, playing too. Caillou tries to get Grandpa involved in the game, which involves Gilbert batting a piece of string, but Gilbert ignores it and walks away. Grandpa comments that Gilbert must have decided that the game is over. At first, Caillou is a bit upset by this, but then he gets a new idea for a new game, he'll pretend to be Gilbert. Just then, Gilbert shows up again, but now Caillou's annoyed because he's interrupting his pretend game and shoos him away. Caillou and Grandpa decide to go inside for lemonade. Caillou notices that Gilbert's water and food dish is running a bit low, so he fills it back up. Once they go back out, Grandpa takes a nap. That night, Caillou notices that Gilbert hasn't touched his food. He calls for Gilbert, but Gilbert doesn't show up. Daddy goes outside to check for him before bed, but he's nowhere to be found. The next morning, he still isn't back. Everyone searches outside for him and Caillou hears a meowing sound and Mommy looks in the bushes, but it turns out that it's actually Sarah's cat, Ollie. Daddy and Caillou head over to the animal shelter, thinking he might be there. He meets a parrot named Bernie who can imitate the sound of a bell and just about anything he hears. Seeing the parrot, he imagines having a different animal as a pet. After thinking about what it would be like to have an elephant, a skunk, or a kangaroo for a pet, he decides that he's quite happy with Gilbert. He and Daddy show the lady at the counter a picture of Gilbert. She notes his collar, which will make him easy to identify. She says that she doesn't have any cats like Gilbert on file, though, but they're welcome to go and check. They do, but he's not there. The lady at the counter says that she'll keep an eye out. Disappointed, they return home and find Gilbert! Caillou tells him he shouldn't stay out past his bedtime.
- This is the first episode to use Adobe Flash animation in-house.
- When Ollie Runs Away Sarah Has The Sound That Rosie Saying "Oh".