When a flash flood washes up a bottle that contains an invitation to a party, the goat and the duck decide to hop in their boat and travel downstream to the beach. So they pack some snacks and a bale of hay and let the river take them. Along the way, they encounter new friends and decide to bring them along. But will their old friends be there as well? And will they get there before the party ends? When they finally arrive at the beach the party is over. But they have a brilliant idea: why not bring their new friends home with them and have a party of their own?