Updated: Sherlock season 4: Trailer, cast, release date, spoilers and everything . The premiere episode - titled 'The Six Thatchers' - aired on January 1, . Sherlock's third series finale hinted at the introduction of a third Holmes sibling. Premiere "Mein Freund WIckie" Doch den krönenden Abschluß fanden die beiden Sherlock Holmes Blockbuster im Kino mit Robert Downey jr. und Jude Law. Sherlock Holmes and Dr John Watson's adventures in 21st Century London. A thrilling, funny, fast-paced contemporary reimagining of the Arthur Conan Doyle.