Chief Gillespie: Virgil, that's a funny name for a nigger boy that comes from Philadelphia. What do they call you up there?
Virgil Tibbs: They call me MISTER Tibbs!
In the wide angle shot of Chief Gillespie approaching Virgil Tibbs at the train station, there is a dog on the platform, in between Gillepsie and Tibbs. In the next shot, a closer view of Gillespie approaching Tibbs, the dog is gone.
Norman Jewison asked Rod Steiger to chew gum when playing the role of Gillespie. Steiger resisted at first but then grew to love the idea, and went through 263 packs of gum during the shooting of the film.