Takes place in the same time line as "Skyline" (2010), in fact some scenes from the first film are in this film, but from different perspectives.
The subway scene is filmed on the Toronto Transit Commission's lower Bay Street station. It is a deserted lower level of Bay Street station and has been used in many movies. The clear giveaways are the signage, font and colours which are typical on the TTC.
The Blu-ray format includes a writers' Commentary. They propose a drinking game with one shot for each production name in the opening credits. Another drinking game would be to take a shot each time one of the writers says "you know" and/or "like". You would probably need a bigger bottle: perhaps a magnum or three.
The movie reunites Frank Grillo and Callan Mulvey who both played Hydra agents in the Marvel Cinematic Universe.
Reunites Frank Grillo and Betty Gabriel. The both starred in Purge:Election Year together.