Filming for the next season of "Sherlock" is well under way at 221B Baker Street.
Actor Toby Jones, best known for playing Truman Capote in the biopic "Infamous," will guest star in the British mystery series as a new enemy to the Great Detective.
"I'm excited and intrigued by the character I shall be playing in 'Sherlock,'" Jones told BBC on Monday.
While there are few clues about the new season of "Sherlock," BBC did reveal that Jones will appear in the second of the season's three episodes.
"Delighted to have Toby Jones on board, bringing to life one of Doyle's finest villains," co-creator, writer and executive producer Steven Moffat told BBC.
The episode will be directed by Nick Hurran, who was Emmy nominated for Outstanding Directing for a Miniseries for a "Sherlock" episode from season 3.
The returning characters are Sherlock Holmes (Benedict Cumberbatch), Dr. John Watson (Martin Freeman), Mycroft Holmes (Mark Gatiss), Molly Hooper (Louise Brealey), and Mary Watson (Amanda Abbington), Mrs. Hudson (Una Stubbs) and DI Lestrade (Rupert Graves).
An air date for season 4 has yet to be announced.