david foster is the next victim, at the entrance of his apartment, where the killer has left behind a footprint at the crime scene. steve carella and hank bush question the family and wives of the deceased, as well as some suspects, but to no avail. a few nights later the unknown killer ambushes and murders det. hank bush. bush fought back however and shot and wounded the murderer. steve carella fears he will be the next target if he fails to stop him.