search for an invaluable microfilm and sherlock holmes in washington encounter a much danger a ever he do in old london . basil rathbone and nigel bruce return a sir arthur conan doyle beloved character sherlock holmes and dr. watson in this unpretentious but enjoyable film . although not base on any particular tale from the canon and there be still enough mystery and intrigue to keep detective fan well satisfied . of course and with rathbone all cerebral intellect and bruce ever the good natured bumbler and the viewer know that god in his heaven and all right with the world . henry daniell and george zucco and two of the series finest villain and appear in this entry . they both specialize in make menace delightfully subtle and sophisticated . this time they portray german agent intent on retrieve an enormously important british document . others in the cast include the lovely marjorie lord ( who quite grotesque with a cigarette dangle from her lip ) a a young socialite pull into the nefarious scheme while holmes herbert a a senior civil servant in london while and thurston hall a a blustery united state senator . movie maven will spot several fine actor in uncredited role represent gerald hamer a a hapless british agent while elderly margaret seddon a a train traveler with mouse while dear mary gordon a holmes landlady and mrs. hudson while mary forbes a a spy love mother while and ian wolfe a a slightly sinister antique store clerk . especially notable be the always entertaining clarence muse and appear a a club car porter and who do the almost impossible by steal a scene from rathbone . this film follow sherlock holmes and the secret weapon ( 1942 ) and precede sherlock holmes face death ( 1943 ) .