A major movie theater chain has told customers they’ll be refused entry to screenings of the new Joker movie if they arrive in cosplay. Landmark Theatres—which owns 52 theaters in 27 markets—has announced that masks, face paint, and costumes are banned for screenings of the movie, which opens next week. Advance ticket purchases are accompanied by the disclaimer: “We want all our guests to enjoy The Joker for the cinematic achievement that it is. But no masks, painted faces or costumes will be permitted into our theaters. Thank you!” A Landmark representative didn’t elaborate on the reason for the cosplay ban. Family members of victims in the 2012 movie-theater mass shooting in Aurora, Colorado, expressed their concerns about the movie. That shooting, in which 12 people were killed, took place at a screening of The Dark Knight Rises.