The painting featured in the movie at the beginning is titled "The Triumph of Death".
The title of the movie is inspired on the quote of First Thessalonians 5:2, which says "the day of the Lord so comes as a thief in the night".
When shooting the scene where Paul interrogates Will, the boom operator had to sit in a tree for half the day to record the audio correctly.
There is a picture hanging in the hallway that is a tribute to Lil Wayne's Carter IV.
One of the pictures in the hallway is of Bill Withers, the singer famous for the hit song, "Lean on Me."
Joel Edgerton's character states that he was a teacher before the world started falling apart. Joel Edgerton's character was a teacher in the movie Warrior (2011).
Both Carmen Ejogo and Riley Keough also play in the anthology series The Girlfriend Experience, though their characters appear in separate seasons of the show.