Factual error: During the scene where Charlie's thug, Lo, is in the street with the homeless man and his "busket", Lo gets angry at him, pulls his Glock out and rakes the slide to chamber a round. However, in the next shots of Lo we see his Glock with the slide still back even though it should have returned to the closed position.
Revealing mistake: During the flashback scene where Max is describing the night of the kidnapping, the rainfall at the marina is obviously fake. The "rain" is being blown at an odd angle from an off-camera fan, and the surface of the water is practically still with no raindrops. (00:40:50)
Charlie Barret: I'm going to give you an opportunity: get out of this. Now. Before it gets so fucked up nobody could ever recover.
Charlie Barret: Ira, come here. You are the man. Remember that. Okay.
Ira Reder: That's fresh ice. That's very cold.
Question: Much ado is made near the start of the film about the kidnappers sending Elise's finger back to her family as a threat, but we learn later that she was never harmed. Did the film ever explain where the finger actually came from, or if it was even sent at all?