Lassie and her new pal, a mutt named Skipper, are getting along just fine with Reed and Johnny, a couple of guys they befriended on the beach, until John discovers Reed is ""the law,"" a harbormaster, and walks out. But he finds he needs ""the law"" later on when he ""borrows"" a for-sale cabin cruiser and takes Lassie and Skipper along for the ride.