Caillou's in the garden with mommy when Sarah comes over and shows Caillou her magnifying glass. Caillou and Sarah plays jungle explorer, pretending that a caterpillar is a jungle monster and Gilbert is a ferocious lion. Caillou and Sarah then hears a really loud noise. Caillou thinks that it's jungle drums, but Sarah thinks that it's just thunder. Caillou then go relates his story to mommy, who tells him that the noise is sending them a message: go indoors lest you want to get wet. The end.