9 girls, living 9 completely different lives and who never have crossed paths before receive the same harrowing letter in the mail containing the address; mapo-gu yeonnam-ro 22, 2nd floor in cheongdam, written by an anonymous author.
all 9 get on at different stops but ride bus 4491 to the same destination.
the address is found to be a male residency currently housing 9 house mates.
as more and more letters begin to arrive and terrifying ordeals occur, no one is allowed to leave the residence within the time constraints of 9am-9pm.
the 16 of them must work together to uncover the hidden truths of the contents of the letter.
but none of this will end until the true reciever of the letter is found.
--4491 | Stray Kids AF.