Because of a bet, Billy is in the uncomfortable position of having to eat fifteen worms in fifteen days. The worms are supplied by his opponent, whose motto is "The bigger and juicier, the better!" At first Billy's problem is whether or not he can swallow the worm placed before him, even with a choice of condiments from peanut butter to horseradish. But later it looks as if Billy will win, and the challenge becomes getting to the worm to eat it. Billy's family, after checking with the doctor, takes everything in stride. They even help Billy through his gastronomic ordeal, which twists and turns with each new day, leaving the outcome of the bet continually in doubt.


比利因一場賭注而落入窘境：他必須在十五日內吃十五條蟲。這些蟲將由對手提供，而對手的格言就是『蟲就是要大又多汁』！雖然比利能選擇要拌花生醬還是芥末等醬料，但他首先要面臨的，還是在於到底有沒有辦法將眼前的蟲吞下肚。隨著故事的發展，比利看似勝券在握，但對手卻開始出招阻撓比利吃蟲。而比利家人與醫生諮詢後，便欣然接受他參與這場賭注。家人甚至協助比利面對蟲子大餐的折磨，這讓故事每天都有意料外的進展，比利能不能贏得賭注呢？