In solving the case of a murdered woman, our CSI's end up catching a serial killer who then points them to another victim whom he didn't kill. The woman left her husband and is found dead, making her husband the prime suspect. Our CSIs trace her last days and find she was staying with a male friend before he murder that is found to be a serial killer. He claims that he didn't kill his friend and that her husband is the real killer in her case. Also an ex-con that Mac and a former partner Hunt (played by Peter Fonda) put in jail ends up stalking Mac; Mac reaches out to his old partner for answers but realizes he is hiding something.