Claude Chabrol thought that New York, home of Ed McBain's "87th Precinct", was too unwieldy, so big that it would obscure his intimate explorations of character and swallow the movie, so Chabrol instead relocated Ed McBain's "87th Precinct" to Montreal, Canada which spoke his native tongue of French but still had a North American setting. Despite being set in Canada rather than the USA where Evan Hunter's source novel was set, the movie still retained the "87th Precinct" for the picture.