: Available on Hulu , Disney+ , AMC+ , Britbox , and PBS Passport .
" The Six Thatchers " is the first episode of Sherlock's fourth season, originally airing on January 1, 2017. It follows Sherlock Holmes as he investigates a series of bizarre destructions of Margaret Thatcher busts, a case that eventually unearths dangerous secrets from Mary Watson’s past as an assassin. Where to Stream (United States)
As of April 2026, you can watch Sherlock Season 4, Episode 1 on several platforms:
: Accessible via Amazon Prime Video , The Roku Channel , and YouTube TV .
: Available for purchase (approx. $4.99) on Apple TV and Fandango at Home . Key Plot Points Google Watch Action Data