In this gripping suspense film, Ma Shan (played by Wen Jiang) is a Chinese detective who wakes up one morning after indulging in too much alcohol at his sister’s wedding celebration, only to realize that his firearm is missing. Given that only law enforcement officers are permitted to carry guns, Ma Shan is deeply concerned about the potential dangers posed by the theft. Determined to retrieve his weapon, he embarks on a quest to track it down. However, the recollections of Ma Shan’s friends about the wedding are as unclear as his own, and no one remembers who drove him home. The tension escalates when Ma Shan’s ex-girlfriend visits the town and is soon discovered dead, shot with bullets that match those from his missing gun.