Dominic Fumusa is headed to CBS.
The actor - best known for his role on Nurse Jackie as the title character's ex-husband, below - will guest star on the Elementary Season 1 finale as Mr. Gerard, the bodyguard of a Greek politician (played by Arnold Vosloo).
Look for Sherlock, as you might expect, to discover that Fumusa's character is protecting both his client and some has secrets.
The two-hour Elementary finale airs on May 16 and will include both flashbacks to Irene Adler and a storyline based around Moriarty.
TV Guide first broke this piece of Elementary casting news.