The real mystery of ‘Sherlock’ special? The air date

The sleuths behind “Sherlock” still can’t deduce the air date of a highly anticipated Victorian special.

The PBS Masterpiece hit drama, which has taken an 18-month-hiatus since its Series 3 finale’s air date, returns “soon-ish” with a blast from the past special that transports its titular character and danger-drawn sidekick back to Arthur Conan Doyle’s Victorian London.

Teasing the special with a short clip at the Television Critics Assn. summer press tour in Beverly Hills on Saturday, writer-producer Steven Moffat, wife and executive producer Sue Vertue and series producer Rebecca Eaton couldn’t reveal any details.

FULL COVERAGE: All the news from the TCA summer press tour

They are “going to put it on television and you’ll be able to watch it. And it’s full of spoilers,” Moffat quipped.

What we do know is that there will be three more “Sherlock” episodes, in the tradition of its previous seasons that will follow the one-off Victorian special. Season 4 is in production for this spring in will air “sometime-ish” in the future,” Eaton said.

“Nonetheless, we’re basically not telling you anything,” Moffat added. “We’re aiming for no cognitive content today.”

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The lack of finality appears to hinge on the BBC’s decision to air the 90-minute special in Britain, which is mired in its own license fee and subsidy issues. British media reports have speculated a Christmastime air date, but the panel wouldn’t confirm or deny the reports.

“Sherlock’s” increasingly famous star and Oscar nominee Benedict Cumberbatch appeared at the panel remotely in a self-deprecating “no comment”-heavy video. His costar, Martin Freeman, dropped out of the live appearance at the last minute because of illness.

Aside from the running mystery swirling around the special’s air date, Moffat revealed that transplanting his characters back in time to Doyle’s original era has proved to be a relatively easy feat -- if not “a mistake” they’ve been “a long time rectifying” -- aside from the issue of his female characters’ dearth of dialog. He did appear to tease that the special might hinge on a mysterious specter.

“The main difference is ghost stories work better in the Victorian setting,” Moffat explained. “There are creepy and scary stories from the Doyle era and it’s easier to do a ghost story. Other than that it’s remarkably similar.”

Cumberbatch’s mind-palace dweller and his acerbic best friend have spent three seasons in present-day London, relying on technology (and numerous text messages) to solve their cases. They obviously won’t be using their cellphones in the 1800s, though Moffat joked that they haven’t ruled out ear trumpets.

“They’ve done a tiny change to the way they speak,” Moffat said. “Sherlock Holmes has the manners of a Victorian gentleman, so he’s a lot less brattish and Watson is a bit more upright. The show is a little more polished.”

Follow me on Twitter @NardineSaad.

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