Sherlock on Masterpiece

PBS | 9:00 pm

Fans of Benedict Cumberbatch and Martin Freeman as sleuth Holmes and Dr. Watson can rejoice over an encore of their brief Season 4 of their take on the detectives. The first of the mysteries, "The Six Thatchers," refers to former British Prime Minister Margaret Thatcher … whose image is being targeted by someone with a possibly larger purpose. Rupert Graves also returns to the cast, and Lindsay Duncan guest stars.