Here's the official guide of Elementary episode 12 titled "M" -- airing on Thursday, Jan. 10th on CBS.
SHERLOCK HOLMES COMES FACE TO FACE WITH “M.,” A BRITISH CRIMINAL WHO APPEARS TO HAVE FOLLOWED SHERLOCK TO NEW YORK ---
Vinnie Jones Guest Stars as “M.” a Criminal with Strong Ties to Sherlock’s Mysterious Past
- Sherlock is reunited with “M.” a British criminal who appears to have followed Sherlock to New York.
- Meanwhile, Joan has reservations about leaving Sherlock and taking on a new client.