Watson is an NPC who lives in Hosidius House in Great Kourend. He can be found in the building west of the western-most Hosidius bank, or south of the Hosidius Estate Agent. Players can trade him one each of easy, medium, hard, and elite clue scrolls to receive a master clue scroll.
Watson's house also contains a noticeboard where players can view a list of the STASH units they have built and/or filled.
Watson's name is a reference to Dr. John Watson, partner of the famous fictional detective Sherlock Holmes.