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SAN DIEGO — Moriarty made a surprise appearance at San Diego Comic-Con on Thursday.

Actor Andrew Scott, who plays Sherlock's nemesis, was unable to be on hand in person for the panel, during which secrets about the upcoming Sherlock special were revealed, but he sent a special video message for fans in attendance. It features some very special guest stars Sherlock fans will be excited to see — and even a bit of Shakespeare.

Watch it above, exclusively on Mashable.

The Sherlock Special does not yet have an official premiere date but will air on Masterpiece on PBS.

Scott — or his character, at least — has a habit of making surprise appearances. His most recent unexpected pop-up sent Sherlock fans into a tizzy when his character appeared in the final minutes of the Season 3 finale — an event made even more curious considering the character was thought to be dead.

Will he be back? TBD.

What we do know? Sherlock needs to come back ASAP.