It’s definitely plural. The translated title has been released simultaneously in several languages throughout Europe and Latin America, obviously it’s a coordinated strategy.
Milenials are already working in think tanks by 2017. Clearly they can’t come up with a decent spacially and emotionally human scaled plot for a movie but most definitely they will foresee these kind of ruses in marketing techniques about reveals and plot twists on almost every possible matter.
It’s all they know and love to do. Well played.