A woman devoted to her son struggles to keep him from spending his life in prison in this drama from director Bong Joon-ho Do-jun (Weon Bin) is a man in his mid-twenties who isn't especially bright & is easily led Do-jun lives with his elderly mother (Kim Hye-ja) who loves him fiercely even though she has no illusions about his abilities or his bad habits Do-jun spends much of his spare time with Jin-tae (Jin Gu) a borderline criminal who takes advantage of Do-jun's credulous nature much to his mother's annoyance When Do-jun is arrested by police & accused of the murder of a young woman his mother is certain he couldn't have done it & sets out to prove her son's innocence to police detectives who seem more interested in closing the case than researching other possible leads At first mother feels certain that Jin-tae has framed her son to avoid being punished himself but as she digs deeper she suspects the truth is more complicated