Kurt Russell prepared for his role as a reporter by spending time with veteran Miami Herald crime journalist Edna Buchanan and Miami Herald photographer Tim Chapman.
Originally the source material was in a yet unpublished novel form, written by John Katzenbach in 1982. The manuscript then landed on Producer David Foster's desk. Foster optioned it as a film, and the property then got published as a novel named "In The Heat of Summer".
The scorching trumpet solos performed during the Main Title music composed by the legendary Lalo Schifrin were done by Chuck Findley. Herb Alpert, another legendary jazz trumpet player, is featured in the score.
Kurt Russell's character is loosely based on the film's source novelist John Katzenbach, who was a reporter for the Miami Herald.
The real-life Miami Police Department's S.W.A.T. Team appeared in the movie as the Miami Police Department's S.W.A.T. Team, in a scene where Kurt Russell's character enters the house of a victim. Many interiors were also filmed inside the Miami Police Department Headquarters.