The third chapter in a planned anthology about the sinister Lasser Glass, "The Man With the Plan" is actually the first installment to be filmed. Of the nine possible chapters to shoot, Mike Flanagan and Jeff Seidman opted for this one purely because of budgetary constraints - the single character/single location nature of this chapter made it ideal. This chapter also gives the viewer a detailed history of the mirror itself, which the filmmakers wanted to include in their first film so that the other chapters would have the proper context.
Production was halted on the final day of production because a shoot-out erupted between police and several armed occupants of the house across the street from the location.
The mirror itself is actually available on line for sale, and is part of the "Howard Elliot" collection. Its frame is actually made of hard plastic.
Filmed in only four days.