余浪沖首次參加水運會，熾熱氣氛下見識到A班兩大主將蛙王羅力森及飛魚黃亞樂的實力。然而余浪沖不忍自己的加入而令C班不和，反過來支持大秋參加個人賽以證實力，更助他奪回接力隊的正選。李馬榮不怒反喜，因為借余浪沖來激發大秋的鬥心，正是他要做的事。Miss翁雖佩服李馬榮的勇謀兼備，卻更擔心他這危險策略的副作用。果然，正當C班眾人自覺形勢大好，阿帆卻因為被急於求勝的李馬榮過度壓逼操練而受傷，別無選擇下只能由余浪沖臨時補上。李馬榮臨危不亂，立即變陣，一反常規地將最強的泳手放在首三棒，以求在賽事早段大幅領先A班，摧毀對方的士氣，並以從未出場的天才泳手余浪沖來挑戰對方最後一棒的王者黃亞樂！
When Ma Wing decides to have Yu Long Chung replace Dai Chau, it leads to a big argument between the teammates. Dai Chau thinks he deserves a fair match with Yu Long Chung, but Ma Wing refuses his request. Ms. Yung sees through Ma Wing's dangerous strategy and advises him of the possible consequences of his plan.
