Sherlock will get back into the swing of things on New Year’s Day, but Season 4 may need another week or so for things to really hit the fan. Our first synopsis for Season 4 midpoint “The Lying Detective” has arrived, as Benedict Cumberbatch’s high-functioning sociopath comes to tangle with Toby Jones’ ominous Culverton Smith.

Where January 1 will fetch Sherlock from the plane to answer the mystery of “The Six Thatchers” (itself an update of Sir Arthur Conan Doyle’s “The Adventure of the Six Napoleons”), a new synopsis reveals the world’s greatest detective (you know, other than Batman) taking on “The Lying Detective” on January 8. The name is presumably a reference to “The Dying Detective,” while the synopsis reads:

In episode two of this new series, written by Steven Moffat, Sherlock faces perhaps the most chilling enemy of his long career: the powerful and seemingly unassailable Culverton Smith - a man with a very dark secret indeed.

Benedict Cumberbatch returns as Sherlock Holmes, with Martin Freeman as John Watson, Mark Gatiss as Mycroft, Rupert Graves as Inspector Lestrade, Una Stubbs as Mrs Hudson, Amanda Abbington as Mary Watson, Louise Brealey as Molly Hooper and Toby Jones as Culverton Smith.

Nick Hurran directed the installment, having previously helmed Season 3 finale “His Last Vow,” along with a number of crucial Doctor Who episodes, from 50th Anniversary “The Day of the Doctor” to Amy and Rory’s final episode, “The Angels Take Manhattan.”

Time will tell if “The Lying Detective” also answers the riddle of Moriarty’s posthumous attacks (we’d bet on “The Final Problem” for that one), but what sinister secret might Culverton Smith be hiding? Watch the trailers below.