What if the only witness to a murder is more twisted than the killer?

Ruby Johnson is a nanny and maid to wealthy families in Manhattan's West 74th Street. She knows their routines. Their secrets. One night, on her way home, Ruby witnesses a neighbour's murder. She knows the victim. She knows the killer. She makes an anonymous call to the police and names the murderer.

But Ruby didn't tell the truth...because there's something wrong with Ruby Johnson. As Ruby's deadly game begins, one thing is certain. It won't be the last murder this witness is involved in...