3rd Degree (A Women's Murder Club Thriller, 3)

In James Patterson's shockingly suspenseful #1 New York Times bestseller, one member of the Women's Murder Club is hiding a secret so dangerous that it could destroy them all.
One of James Patterson's best loved heroines is about to die. Detective Lindsay Boxer is jogging along a beautiful San Francisco street when a fiery explosion rips through the neighborhood. When Lindsay plunges inside to search for survivors, she finds three people dead. A lost infant and a mysterious message at the scene leaves Lindsay and the San Francisco Police Department completely baffled.
Then a prominent businessman is found murdered under bizarre circumstances, with another mysterious message left behind by the killer. Lindsay asks her friends Claire Washburn of the medical examiner's office, Assistant D.A. Jill Bernhardt, and Chronicle reporter Cindy Thomas to help her figure out who is committing these murders-and why they are intent on killing someone every three days.
Even more terrifying, the killer has targeted one of the four friends who call themselves the Women's Murder Club.
Which one will it be?