Crossword clues for Perry who's on the case 5 lettersAnswerClueNIECEThe Case of the Sleepwalker's ___ (Perry Mason mystery)MASONPerry who's on the caseMASONPerry who lost only one case in his careerBLACKMAILCase for Perry Mason.FRAMEUPPerry Mason case, perhapsBLACKMAILBasis of a case for Perry Mason.RETAINERWhat Perry Mason seldom undertakes a case without.ONCEHow many times TV's Perry Mason lost a case