The 5th Horseman is the fifth book in the Women's Murder Club series featuring Lindsay Boxer by James Patterson and Maxine Paetro first published in February 2006.

[1] The story begins with a mysterious character named the Night Walker who kills a hospital patient, Jessie Falk.

Patient whose diagnoses are not putting their lives in danger die continuously; and buttons are placed on their eyes, once dead.

Tied into the strange murders at Municipal Hospital is a court case against municipal which involves a malpractice suit filed on behalf of twenty plaintiffs whose family members died at the hospital due to medication errors or perhaps outright murders.

The ER doctor, Dennis Garza, working in conjunction with the prosecutor, flubs his testimony so that the hospital loses.