Michael and K.I.T.T. are hired by Rita to find Ron, her missing brother, whom she suspects has met with foul play. Their investigation leads them to Michael's evil half-brother Garthe Knight (who looks remarkably like Michael), and Garthe's mother, Elizabeth--sponsor of the Foundation and ex-wife of Michael and K.I.T.T.'s creator/father. Freed from an African prison, Garthe obtains the three-part chemical compound which is responsible for K.I.T.T.'s special molecular -bonded shell. Elizabeth and Garthe adapt this to "Goliath", a powerful, behometh semi-truck. Better watch out, K.I.T.T.