For years, a blackmailer has been preying on the weaknesses of others throughout London. When Holmes hears of the utter misery this mystery man is creating, he adopts a campaign to thwart his evil scheming. The campaign astonishes Dr. Watson by its strangeness and finds Holmes falling in love.
Jeremy Brett
as Sherlock Holmes
Edward Hardwicke
as Dr. John Watson
Robert Hardy
as Charles Augustus Milverton
Norma West
as Lady Diana Swinstead
Gwen Ffrangcon Davies
as The dowager
Colin Jeavons
as Inspector Lestrade
Serena Gordon
as Lady Eva Blackwell
Rosalie Williams
as Mrs Hudson
Sophie Thompson
as Agatha
Nickolas Grace
as Bertrand
Sarah McVicar
as The Hon. Charlotte Miles
David Mallinson
as Colonel Dorking
