Set in the 2000s in a medium-sized Chinese city near the Russian border, the film follows Ding, Sammo Hung Kam-Bo, an elderly, overweight man who becomes entangled in a web of crime and memory after witnessing a stabbing. The police soon suspect that his fading recall and confusion mask something deeper, and his dementia is read as a sign of frailty even as his instincts for self-preservation quietly sharpen.
Back at home, Ding is repeatedly invited to share meals by his land-lord Park, Li Qinqin, an older woman who grows fond of him. He also forms a quiet, protective bond with Cherry, Jacqueline Chan, a bright little girl who lives next door and who often relies on his steadiness. Cherry’s father Li, Andy Lau, is a gambler whose spiraling debt drags him deeper into danger, dragging his family along for the ride.
When Li is squeezed by his creditors, Choi Dong-Hen, Feng Jiayi, the leader of the local gang and a man of Korean descent, forces Li to steal the shoulder-bag of a Russian gang leader. The heist triggers a tense chase and Li escapes with the bag, but his debt remains unbroken and his clandestine life grows more perilous. Choi’s machinations reach further as he has Li’s daughter threatened, prompting a cascade of retaliations between rival criminal factions and furious Russians who believe their territory has been violated.
One night, Choi’s gang assaults Ding’s home after Cherry wanders inside, but Ding proves to be a formidable fighter, repelling the intrusion with surprising prowess. To avoid arrest, two of Choi’s men are sent to hide in the countryside, while the police, noticing Li’s disappearance, relocate Cherry to live with her aunt and uncle. Yet the aunt and uncle soon tire of her presence, and Ding steps in, agreeing to look after Cherry and keep her safe.
Soon after, Cherry goes missing again, and Li reappears at Ding’s door with money to compensate him for his help, only to be ambushed by Choi’s men as he leaves the house. Li dies, and the shoulder-bag slips back into the hands of Choi’s gang. Ding, haunted by years of guilt since his granddaughter vanished on a hiking trip, resolves to retrieve Cherry by force. He storms a gambling house demanding Cherry’s release, and when Choi’s men try to kill him, Ding overpowers around twenty assailants, including a skilled knife-wielding killer.
As the fight spirals outward, Russian gang members arrive to reclaim their stolen money and begin slaughtering Choi’s men. Choi escapes only after sustaining a leg wound. The Russians press the attack, prompting a police pursuit in which two leaders of the Russian faction die when they crash into a waiting truck. Believing himself safe, Choi is subsequently murdered and robbed by two of his countryside associates who have accepted a Russian bribe to betray him.
In the aftermath, Ding’s dementia worsens and the weight of Cherry’s absence paralyzes him emotionally, though the police frame his actions as self-defense rather than crime. Cherry eventually returns, explaining that she simply ran off to a friend’s house. Even as Ding forgets his relatives, he clings to the memory of Cherry and cherishes the care she gives him in his advancing years. After the credits roll, a pair of rural criminals stumble into a group of drilling PLA military police, triggering a chase that ends with their capture.
