Eric and Clive's widowed dad is a steward on a cruise ship, and every time he goes away, the twins miss him terribly. Eric (older and considerably wiser than Clive by about five minutes) and Clive decide that this time will be different. When their father leaves for his latest cruise, they will go with him! Only Dad doesn't know yet, because Eric and Clive are going to be stowaways! How can their plan possibly fail? Okay, so Clive is a compulsive liar, with a tendency toward disastrous mishaps. It's worth the risk. All they have to do is keep out of Dad's way and stay out of trouble -- for three whole weeks...