Directed by: Christopher Landon
Starring: Vince Vaughn, Kathryn Newton, Celeste O'Connor, Misha Osherovich
Revealing mistake: Clearly not Vince Vaughn during the opening kills as the Butcher seems leaner than Vaughn.
Suggested correction: Seems leaner" is just far too vague to be a mistake, and I didn't see anything that made me immediately think he was "clearly not Vince Vaughn.
Revealing mistake: When the shop teacher walks up to Millie at the start of the film and slams the book, as he begins to step in front of her table, you can see him subtly "step down" even though he's on an even floor. Due to technical limitations, there needed to be a raised surface on the floor for the camera, a few inches off the ground. It was painted out digitally, but you can still see the actor step off the platform, making it look like he's "stepping down" on even ground. (Confirmed in Blu-Ray commentary.)
Millie (Blissfield Butcher): I want my body back.
Blissfield Butcher (Millie): Come and get it.
Trivia: Clearly a loving nod to Friday the 13th and Halloween movies here as the Butcher wears a mask similar to Jason's hockey mask in the opening scene, seems indestructible like both Jason and Michael, uses almost anything as a weapon and appears out of nowhere when his victims think they're safe.