It’s raining outside but there is no stopping Caillou! Since no one wants to join him, he goes outside to play in his new froggie boots, his rain coat and hat. He has a great time walking through water, making holes in the wet sand of the sand box, and making mud soup. He sees a robin catch a worm and is thrilled when he finds a worm of his own. When Leo calls to invite Caillou over to play, Caillou isn’t sure at first if he wants to go since he’s having such a great time by himself but, he decides that he wants to show his worm to Leo and heads off to see his friend.