Detective Inspector Rain Frank is looking forward to her retirement soon, having spent the last 12 years catching serial killers in her quiet little town of Coatbridge, her close working and personal relationship with her current partner, Theodore Gillon-Smith, is the only reason she agrees to takes on her last case, hunting two serial killers. Theodore is an adopted son of the Frank family, white, rich and an eccentric young man, together they struggle with everyday issues whilst finding justice for those who had been let down by the justice system. Street wise and brought up in a Black community, she has fought hard to establish a name and reputation as one of the leading female detectives in the Scottish Police Force.