Adapted from manga author Kazuichi Hanawa's autobiographical account of his three-year prison term for weapons and explosives violations (he collected replica guns and took part in simulated battles), this masterly film is a prison movie like no other. Korean-Japanese director Sai (now also known by his Korean name, Choi Yang-Il) heightens the humour but resists any temptation to add violence, melodrama or gratuitous bodily fluids. Centred on the cell Hanawa shares with four other 'hardened criminals', the film explores the codes and daily routines of prison life: meals, laundry, cleaning, baths, exercise, making tissue-box holders in the workshop. The reward for good behaviour is a movie: Kitano's Kids Return, consumed in silence. For Hanawa (Yamazaki, excellent), the real epiphany is the time he spends in solitary, his punishment for 'unauthorised communication' with his cell-mates - which means noting down their names and addresses. If Ozu had ever made a prison movie, it would have felt like this.