Two cops heard the desperate screams of the Chinatown woman who was stalked by a homeless stranger and murdered in her apartment — and even spoke to her killer through the door — but failed to help, the victim’s family claims in a lawsuit. Christina Yuna Lee, 35, was attacked by an assailant who snuck in behind her as she entered her Chrystie Street building around 4:20 a.m. on Feb. 13, 2022. Neighbors heard her cries for help “for at least five minutes” as she was being viciously butchered, and dialed 911.