With Grissom teaching at a conference, Nick Stokes and the remaining CSIs investigate a murder of a family in a house in a small town outside Las Vegas. In the house there is evidence of violence, blood and gunfire. The rest of the team thinks that the entire family was murdered, but Nick has the feeling that the little girl, Cassie, is still alive. So they start investigating and discover the motive of why the family was murdered, an illegal green house full of pot; and find a wrapped piece of chewing gum in every place they go while searching for clues. So Nick believes that Cassie left them telltale clues in the form of gum drops.
—James_ Corck