A private detective, Bill McCabe, arrives from Australia to investigate a claim that Arthur is heir to a fortune left by an distant relative who's died intestate. Ray and Arthur carry out some genealogical research at the Family Records Centre (then located at St. Catherine's House and now merged with the National Archives), and also search parish records. They finally locate what appears to be clinching evidence of Arthur's claim to be the last surviving descendant of the deceased's family. But the Will requires the inheritor to be ‘of good character', and Arthur has just been charged with unauthorised use of parking infringement notices (which are also forged).