這是一個平凡人為愛妻赴湯蹈火的冒險故事。電腦工程師李恩郎（胡鴻鈞飾）與太太趙卓穎（劉佩玥飾）過著平凡幸福的生活。一個早上，恩郎與卓穎突然被黑道擄走，聲稱恩郎侵吞了他們一億元，命他在72小時內交還，否則殺死卓穎！摸不著頭腦的恩郎，報警時重遇昔日宿友，熱血幹探梁曉揚（伍富橋飾）與中學時暗戀對象唐美蘭（朱智賢飾），美蘭還隨恩郎踏上救妻旅程。明查暗訪下，終得知一切均與恩郎過去曾入住的青年宿舍有關，當年與宿友一起經營的網上交易平台，竟然成為洗黑錢平台。二人為揪出幕後黑手，逐一調查當年入住過的宿客，過程中勾起昔日宿舍往事，並把目標鎖定在張梓健（黃庭鋒飾）身上。救妻期限將至，真相愈發接近，恩郎發現美蘭、曉揚、梓健，甚至卓穎，都有不為人知的一面⋯

The story revolves around and ordinary man who risks himself to save his beloved wife. Computer engineer LEE YAN-LONG (Hubert Wu) and his wife CHIU CHEUK-WING (Moon Lau) lead an ordinary happy life until one day they get kidnapped by thugs, who threaten to kill CHEUK-WING, unless YAN-LONG repays them $100 million within 72 hours! Bewildered, YAN-LONG reports it to the police, thus re-encounters his former roommate, now hot-blooded detective LEUNG HIU-YEUNG (Alvin Ng) and high school crush TONG MEI-LAN (Ashley Chu). With help from MEI-LAN, YAN-LONG uncovers that everything is related to the youth hostel where he stayed years ago, and the online trading platform he ran with other roommates has become a money laundering hub. They investigate those that stayed in the hostel in search of the culprit, triggering memories of the past, and all the evidence seems to point at CHEUNG TSZ-KIN (Telford Wong). As the deadline approaches and the truth is just one step away, YAN-LONG discovers that each of them including his own wife has a secret side to themselves……