Ian Carmichael ("Jack") and his fiancée "Peggy" (Janette Scott) fall foul of her rather fastidious landlady and are soon looking for a house. As luck would have it, they discover a houseboat and for a mere £750 they have their dream home/yacht. Not long after moving in they meet their landlord "Watson" (Dennis Price) who wants to double the rent for their mooring. Extortionate, so he - a mechanic, encouraged by his pal "Sid" (Sidney James), decides to g...