Grissom, Sara and Warrick are called in to investigate an abandoned, blood-splattered apartment and Nick and Catherine must examine a dead scuba diver lodged in a tree. The team members are suspicious when the former tenant of the bloody apartment claims that his missing girlfriend is visiting her parents -- and the parents say she never showed up. Meanwhile, Nick and Catherine are called to the site of a large fire and are confronted with the scuba diver found dead in the top of a tree near Lake Mead. Is it a murder or an urban legend turned fact?