Director Andy Ng (Operations Billionaires), this movie revolves the Tactical Unit main characters, Simon Yam, Maggie Shiu and Lam Suet, in which showing the friendship between Unit members. 4 mobsters from mainland are on the way to an armed robbery and they meet up Sam (Simon Yam) and May (Maggie Shiu) from the PTU. The PTU is beaten up and 4 mobsters escape. In order to get rid of his debtor, Police officer Fatty (Lam Suet) moves to a motel and becomes very close to 4 residents next door. They are actually the 4 mobsters and invite Fatty to join their project. Fatty feels he has been given up by his teammates and families, at the moment his conscience becomes unclear. In the confrontation between PTU and the mobsters, how will he decide his path?