Many scenes were set in subway stations. Calgary does not have a subway system. The city's light rail system is mainly above ground, as are all 36 stations.
Shots in the Montreal subway's were clearly done at night as newsstands in the main station are closed while it is supposedly a normal work day.
Although significant efforts have been made to disguise Montreal's subway as Calgary by replacing almost all signs and advertisements with English-only equivalents, we can still some references to Montreal in some shots. For instance, we can see a map of Montreal on the wall at one subway's entrance, there is a regulation sign on the wall with reference to STCUM (Société de Transport de la Communauté Urbaine de Montréal), and there is a warning sign in one vehicle with at least one sentence in French.