Snakes

A baby rattlesnake is found in the throat of a decapitated head. In order to catch the killer, the CSIs put themselves into the world of narcocorrido, a Mexican musical lifestyle that idolizes violent acts and brutality. Meanwhile, Sofia and Greg investigate the death of a woman found dead in the front seat of a handicapped van at a casino. They soon discover that the shooter had to have been confined to a wheelchair, narrowing the search.