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The book that McCall is reading on the train at the beginning of the film is "Between the World and Me" by Ta-Nehisi Coates. It won the 2015 National Book Award for Nonfiction.
Denzel Washington wanted the fight scenes he participated in to be as realistic as possible. So they brought in fighter Tyron Woodley to train Denzel for his fight scenes.
During filming, the crew whimsically referred to the movie as "The Sequelizer."
In July 2018, when asked about the possibility of The Equalizer 3, Antoine Fuqua expressed interest in returning to direct.