Mac tries to unravel the circumstances surrounding a bridegroom's murder. Stella receives a jigsaw puzzle spattered with blood.
When Mac's motor racing hero is killed during a race, the CSIs immediately suspect foul play.
The team investigates a murder tied into a string of spy-themed robberies targeting the elite, while Mac continues to receive mysterious calls.
The team investigates the death of a woman who drowned in a self-cleaning toilet.