The Sign of Four poster
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The Sign of Four

6.519831h 37mNRMovieAdventureCrimeMystery

Sherlock Holmes and Dr. Watson try to track down the Great Mogul, the second-largest diamond in the world.

DirectorDesmond Davis
WriterCharles Edward Pogue
ProducerOtto Plaschkes

Where to watch

Amazon Prime VideoAmazon Prime VideoAmazon Prime Video with AdsAmazon Prime Video with AdsJustWatch TVJustWatch TVFawesomeFawesomeThe Roku ChannelThe Roku ChannelYouTube FreeYouTube FreePlexPlexPlex ChannelPlex ChannelFilmzieFilmzieTubi TVTubi TV
Availability shown for United States · rights vary by country

Cast · Directed by Desmond Davis

IRIan Richardson
Ian Richardson
Sherlock Holmes
DHDavid Healy
David Healy
Dr. John Watson
TWThorley Walters
Thorley Walters
Major John Sholto
MOMichael O'Hagan
Michael O'Hagan
Mordecai Smith
CLCherie Lunghi
Cherie Lunghi
Mary Morstan
JMJoe Melia
Joe Melia
Jonathan Small
TRTerence Rigby
Terence Rigby
Inspector Layton
CMClive Merrison
Clive Merrison
Bartholomew Sholto
RHRichard Heffer
Richard Heffer
Thaddeus Sholto
JBJohn Benfield
John Benfield
McMurdo
GRGordon Rollings
Gordon Rollings
Mr. Sherman
JP
John Pedrick
Tonga

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More from David Healy · Co-star actor

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More from Desmond Davis · Director

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The Sign of Four — streaming FAQ

Which OTT platform streams The Sign of Four?

The Sign of Four is streaming on Amazon Prime Video, JustWatch TV and Fawesome in United States, and available to rent or buy on Amazon Video and Fandango At Home. It's not currently on Netflix.

Is The Sign of Four on Netflix?

No, The Sign of Four is not on Netflix in United States as of September 2026. It's currently on Amazon Prime Video and JustWatch TV.

Is The Sign of Four on Amazon Prime Video?

Yes — The Sign of Four is included with an Amazon Prime Video subscription in United States as of September 2026.

Where can I watch The Sign of Four for free?

The Sign of Four is available to stream free (with ads) on JustWatch TV and Fawesome in United States.

Is there a sequel to The Sign of Four?

The Sign of Four is currently the latest film in the Sherlock Holmes (Ian Richardson) Collection.

Is there a prequel to The Sign of Four?

Yes — The Hound of the Baskervilles (1983) comes before The Sign of Four in the Sherlock Holmes (Ian Richardson) Collection.

Is The Sign of Four part of a trilogy?

No — The Sign of Four is part of the Sherlock Holmes (Ian Richardson) Collection, which has 2 films.

How many movies are in the Sherlock Holmes (Ian Richardson) Collection?

There are 2 films in the Sherlock Holmes (Ian Richardson) Collection: The Hound of the Baskervilles (1983) and The Sign of Four (1983).