Curtis Lupo

When high school students start dying from accidents related to "powerballs," a combination of anabolic steroids and methamphetamines, Walker hits the classroom as a substitute teacher in order to try to uncover the source of the drugs and stop the deaths.

A genetic engineering scientist, who has discovered an advanced DNA that could end all genetic disease, is kidnapped by members of a ruthless conspiracy.

Walker steps in when the Mafia strong-arms a local supper club in laundering money.

A statue is shedding what appear to be real tears and Walker must find out why.

Nash and Joe are plunged into the underground world of steroid-crazed body builders when they investigate the murders of three body builders. Nash and Caitlin struggle to define their relationship as Cassidy struggles to get her feet back on the ground after her accident.