Anna Maxwell Martin stars in the last of Jimmy McGovern's dramas, which in a break from the usual format provides a link with last week's episode (so that means more Robert Sheehan - yaaay). She stars as happily married mother-of-three Tina, who works as an officer in a young offenders' institution. One cold morning she oversees the transfer of a new inmate but her sense that things are not quite right turns out to be an understatement. However, her problems have only just begun; Tina becomes the victim of a terrible crime forcing her to take the law into her own hands - and leading her eventually into the dock herself.