Fandom friend Toby Jones has joined Sherlock series 4, showrunners announced Monday.

Jones — who played Claudius Templesmith in The Hunger Games, Dr. Arnim Zola in Captain America and Agent Carter, and voiced Dobby in the Harry Potter series — has been cast as a villain in Sherlock series 4.

The actor will make his Sherlock debut in episode 2 of the fourth series, which we’re learning today will be directed by Nick Hurran, who helmed series 3’s “The Last Vow.” While we don’t know exactly which Sherlock villain Jones is playing, Steven Moffat and company offered these coy remarks: “Delighted to have Toby Jones on board, bringing to life one of Doyle’s finest villains,” said Moffat. Added producer and co-star Mark Gatiss, “We’re thrilled to welcome one of our finest actors to the Sherlock family. I know Toby will embrace the part with true relish!”

Said producer Sue Vertue, “Great to have Nick Hurran back after his fabulous work in series three, and I’ve been wanting to work with Toby for ages, so this is a real treat.”

While there are dozens of potential Sherlock villains Jones could be playing, one specific guess that may match the “finest villains” description is Sebastian Moran. The character first appeared in Sir Arthur Conan Doyle’s “The Adventure of the Empty House” and is the right-hand man of James Moriarty. Sebastian has already appeared in CBS’ Sherlock series Elementary.

Sherlock series 4 already has episode 1 in the can. The latest season of the Benedict Cumberbatch and Martin Freeman-led drama is expected to air late this year or early next.

Who do you think Toby Jones will play in ‘Sherlock’ series 4?

“Promising laughter, tears, shocks, surprises and extraordinary cases, it was announced last month that series four will begin – with the nation’s favourite detective, the mercurial Sherlock Holmes, back once more on British soil – as Doctor Watson and his wife, Mary, prepare for their biggest ever challenge — becoming parents for the first time,” says the BBC.

Recognize Jones from other projects? He’s also been in Fox’s Wayward Pines (Dr. Jenkins) and the BBC’s Doctor Who (in 2010 as Dream Lord).