ddd MissMaryMorstancontactsSherlockHolmesforhishelpregardingherfather,captainMorstan,whodisappeared10yearsago.Sincehisdisappearancesheannuallyreceivesavaluablepearlbypostfromanunknownperson.ThemysteryleadsHolmesanddoctorWatsonintoanintricateplotregardingalosttreasurebelongingtofourconvictsontheAndamanIslands
