The episode starts where Caillou's parents get ready for a party. Rosie tells her Mom that she's pretty and Mommy hands Rosie a Scarf. Caillou asks his dad who's gonna babysit him and Rosie? His Dad says that Grandpa is coming and he's bringing a Surprise. Caillou wondered what the surprise could be. Then, the doorbell rings. Caillou and Rosie cheer. Then Grandpa teases Caillou by saying He brought his dirty socks and wants Caillou to wash them. Caillou laughs and says that he didn't bring his dirty socks. Then Grandpa tells Caillou and Rosie to put on their PJs and the surprise was a book about ships. Then Grandpa hands Caillou a Telescope then he sees Gilbert in it and Rosie wants a turn. Caillou didn't want Rosie to drop the the Telescope so he holds it for her. Grandpa tells Caillou about the front and back of the boat. Caillou wonders why the Sailor was telling. Grandpa tells him that he's giving orders to his crew. Grandpa, Caillou, and Rosie pretend to be Sailors. Then Rosie is tired and Grandpa puts her to bed. Caillou imagines being a sailor. After that he hears the thunder. Then his parents arrived back.
Caillou's parents arrived home quickly.