James Moriarty – the so-called “consulting criminal” and evil mastermind extraordinaire – is back from the dead. Or so the powers that really run England believe after video screens all over the country are hacked to broadcast a loop of Moriarty delivering a simple message. “Did you miss me?”

Sherlock Holmes is naturally skeptical that his sworn enemy is still alive, having witnessed his suicide up-close. He believes, however, that Moriarty would be more than willing and able to design a conspiracy that would go beyond his death and that Sherlock himself is the most likely target for revenge. This leaves Sherlock with little to do but wait for Moriarty’s plan to make itself evident as he solves whatever mysteries attract his attention.

For a time things continue as Sherlock likes them. He is solving cases. His friend John Watson is blogging about their cases. And barring little distractions like John and his wife Mary having their first child, requiring Sherlock to attend a Christening and becoming a Godfather, all is right and well with the world.

Then an odd detail catches Sherlock’s attention while in the middle of one of his cases – a broken bust of Margaret Thatcher, seemingly unconnected to the crime at hand. Soon more and more Thatcher busts – all part of the same set – turn up broken. Their trail will lead Holmes back into The Great Game, but with higher stakes than ever before. A game means little if you have nothing to lose, after all.  And Sherlock Holmes has so much more to lose now…

After a year of waiting since The Abominable Bride special, The Six Thatchers seems sadly flat. The exact reason for this remains hard to pinpoint. The direction by Rachel Talalay (who also helmed the excellent Heaven Sent/Hell Bent episodes of Doctor Who‘s Ninth Series) is some of the best this series has seen and that’s high praise indeed! The technical elements are all up to snuff, establishing a thrilling mood throughout the episode. And the core cast of actors – well familiar with their roles at this point – perform as well as you would hope.

I fear the culprit in this case is Mark Gatiss’ script. Gatiss is a wonderfully witty writer and there’s a number of hilarious moments in this episode. Unfortunately, most of the episode is firmly focused on Sherlock and it leaves most of the ensemble cast with little to do but stand around and take up space.

Surprisingly the same complaint could be made of Dr. John Watson. It seems at times that Watson is barely in this episode, despite an entire subplot devoted to what he gets up to while Mary and Sherlock are investigating something that his wife is better suited to advise on than he is. There’s even a gag about how Watson is able to replace himself with a balloon with a face drawn on it without Sherlock noticing. While this is meant to poke fun at Sherlock’s obliviousness during his manic phases, all it really seems to suggest is how easily forgotten Watson is.

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What truly drags this episode down, however, is its ending and the death of Mary Watson. This is not because the moment is shocking, being as it is is heavily foreshadowed with references to the story The Appointment in Samarra and fans of the classic stories by Sir Arthur Conan Doyle know that Mary Watson dies at some point. The problem is that Mary’s death seems pointless beyond serving a vessel of angst for both John and Sherlock.  This proves doubly problematic as Mary is the strongest female character on the show and there’s no way to look at her death as anything but a fridging.

Perhaps the rest of the season will redeem The Six Thatchers. Standing on its own merits, however, this episode proves disappointing. The trappings of Sherlock are still there but it seems as if the heart has been removed, with much of the ensemble cast reduced to playing flat parodies of themselves and Benedict Cumberbatch being forced to carry far too much of the episode on his own.