Grissom and his team are discouraged when they find a pool of blood as they begin investigating the disappearance of a high school basketball star and his cheerleader girlfriend.Grissom's quip that the young lovers may have run off to Mexico is soon quashed by the discovery of drops of blood by Ryan's vacant parking spot at the school. After finding a letterman jacket and cheerleading sweater in the field house and a pool of Ryan's blood nearby, the team tries to determine what went awry.

A deer is illegally killed, and the person found with the body in the back of his truck apparently dressed it in a tutu. The man, who was completely drunk when arrested, was being interrogated by Nick and Brass, and suddently tries to escape and is pepper sprayed. Unfazed by the spray, officers then taser him and he bursts into flames and dies. Meanwhile an unbalanced woman wearing a tinfoil outfit at the front desk tries to warn people (including Nick) of an alien invasion. After observing the burning man, she later turns up dead with green-tinted blood. When other people turn up with the same problem, it's up to the team to figure out why. Meanwhile, an old couple dies, apparently in their sleep... but there is evidence the cases are related.

When a seasoned sky diver is paralyzed after free falling to earth when his parachute doesn't deploy, he turns out to be linked to the strange death-by-airborne-toxins of two wealthy men with ties to Iran.