Parker Wayne was a Navy Captain who died of a heart condition four months prior to the events in "Head Case". However, instead of being cremated, his remains were used in an illegal chop shop specializing in selling human parts while some remains composed of ash and peddles were given to his family instead. By pure chance, NCIS who were busting three sailors involved in the running of an illegal motor pool/chop shop came across Parker's head in the cooler of the back of a car and opened an investigation.