Instant rivals from day one, headstrong police cadets Chung Lap Man (Roy Ng) and Wai Pa Kiu (Sammul Chan) compete over every little thing, but they can agree on one matter - their mutual enmity for instructor Lee Man Sing (Michael Miu). Peeved by Lee's unreasonable training methods and harsh punishments, the two team up to plot revenge, gradually developing a close friendship along the way. Lap Man and Pa Kiu also encounter romantic interests in brassy canteen worker Fa (Tavia Yeung) and fellow cadet Oi Lam (Fiona Sit), a spoiled rich girl struggling to graduate. Over 27 weeks of grueling training, the willfulness of youth slowly but surely gives way to teamwork, discipline, and determination, and even Lap Man and Pa Kiu begin to understand Lee's tough love. But will Pa Kiu be so forgiving when he discovers that Lee is actually his father?