Sherlock Season 4 Plot
The fourth series begins with the nation’s favourite detective, the mercurial Sherlock Holmes, back once more on British soil, as Doctor Watson and his wife, Mary, prepare for their biggest ever challenge - becoming parents for the first time.
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Prices last updated October 8, 2026. Pricing and availability may vary by region.
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Season 4 Episodes
3 episodes
1
70
The Six Thatchers
Why is someone destroying images of Margaret Thatcher? Is there a madman on the loose? Or is there a much darker purpose at work?
2
84
The Lying Detective
Sherlock faces perhaps the most chilling enemy of his long career: the powerful and seemingly unassailable Culverton Smith – a man with a very dark secret indeed.
3
75
The Final Problem
Holmes and Watson travel to Europe to escape Moriarty's vengeance.