The theme of certain members of those in law enforcement being murdered one by one was later featured in the 2014 motion picture "Sabotage", itself loosely based on Agatha Christie's classic novel "And Then There Were None".
Egan and Harriet had a relationship together prior to being assigned as partners at Egan's precinct which did not end well and while they consummate their relationship while they work on the case.
Freeman King who plays IA Detective Ridley is one of the co-writers of the film along with Darren Dalton, who plays one of the crooked cops that Ridley is investigating.
When Egan is on the job, his wardrobe consists of his Detroit Tigers hat, black leather gloves, his brown leather jacket, blue jeans and black shoes. He rarely is seen wearing anything other than that except for a few scenes.
C. Thomas Howell and Darren Dalton are close friends in real life and worked on several movies together going back to The Outsiders in 1982, where they first met making that film which continued to Red Dawn and to this film, in which Dalton was one of the screenwriters and Howell a producer.