 Lt. Bracken brings in an undercover cop named Mary Riggs, who was also a former tennis player.Bracken explains to Holden that Mary is going undercover to pose as a tennis instructor at the college and Kendall is going to assist her whenever he can.As a reporter named Sylvia Costa is stonewalled by Bracken, the killer stalks a girl later that evening, who had finished her dance routine, and saws her arms off inside an elevator just before Kendall and the police arrive.