Cyber-lebrity: When Luke Selyan, boyfriend to famous swimmer Candace Walker, is killed at her swim meet by an arrow shot through his chest, Horatio and his team are plunged into the world of cyber-stalkers and fans who will do anything to get close to Candace. They learn that someone took a photograph of this seemingly ordinary teen in her Speedo and posted it on the Internet, sparking an overnight international obsession with her. They also find the fingerprints of Gil Callem, a blogger and star-stalker, on Luke's sunglasses. Apparently, Callem switched Luke's sunglasses for a pair fitted with a hidden camera to capture photos of Candace.
Natalia and Calleigh discover that the arrow was shot by a female, which leads them to Candace's jealous teammate, Miranda. Miranda had a thing for Luke, but the feeling wasn't reciprocated, which led her to kill. Her target was Candace, but she missed and her arrow hit Luke instead. Horatio falls victim to the celebrity stalker fans when a photo of him at the crime scene shows up online. It also details the fact that Horatio was the investigating officer in a case that put away a big mob boss, and it's clear someone is out to get him. Horatio baits his stalker to meet at an empty warehouse, and the culprit turns out to be the troubled son of the mob boss, seeking revenge.