Catherine, Nick and Warrick investigate a house fire, they first suspect a serial arsonist. The decedant is a teenaged girl. Ironically, her mother has a match collection. But it turns out however, that is was her son, Sam, who did it. He wrote the insault he hears around his house on the floor in Dish Fuel, he struck a match and lit it on fire, killing his sister.
Grissom and Sara deal with a man that is found dead in a public bathroom who died of asphyxia. The autopsy reveals that there is an "S" in the man's trachea.
The find out that this man has five other letters in his stomache, they are letter tiles from the 2004 Western Regional Logos Tournament. He was a cheater and an opponent of his lost a game to him because of that. He wanted him to make him "eat his words" and that's what he did-- and he choked on them.
I thought this episode was really well done, there was a clever plot line for both cases. The first case ended with an interesting twist at the end. The other, just plain bizarre and interesting from the start. "Bad Words" was an excellent episode!