How closely were you watching the new episode? (Picture: BBC)

Sherlock has a history of rewarding the dedicated viewer with references, easter eggs, hints and in-jokes, and The Six Thatchers was no exception.

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Season four got off to a bang, driving a wedge between John and Sherlock and delivering a shocking ending that will no doubt continue to be felt across the rest of the series.

But in among all the excitement, did you manage to keep up your observational skills, like the great man himself? Did you spot these clues and references in last night’s Sherlock?

‘Business – it’s murder’

Toby Jones’ character got a sneaky debut (Picture: BBC)

Next week, The Lying Detective is set to introduce us to Toby Jones’ villain Culverton Smith – but it won’t be the first time we’ve seen him in Sherlock. In this blink-and-you’ll-miss-it easter egg, we can see a bus advert that bears the image of, as Steven Moffat put it, ‘one of Doyle’s greatest villains’.




It doesn’t tell us a lot about Culverton Smith, admittedly, but it does provide a few hints as to the place he occupies in this world; clearly, he’s an individual with a fairly high profile.

The original short story, The Dying Detective, saw Culverton Smith as an expert in diseases and immunology – might he here be some sort of evil David Attenborough or Brian Cox type?

That’s perhaps a little unlikely. Some of Sherlock’s dialogue in the trailer for The Lying Detective is reminiscent of how he previously described Charles Augustus Magnussen, and how Moffat has referred to people like Rupert Murdoch – perhaps Culverton Smith is going to be a similar figure.

‘Put me through to Sherrinford’

Are these the only Holmes siblings? (Picture: BBC)

Sherlock Holmes scholar William S. Baring-Gould once proposed that Sherlock was one of three brothers; a comment in one of the stories that his family were country squires would necessitate that the eldest brother in the Holmes family would tend the estate.

That Mycroft didn’t do this suggested – in a true Holmesian deductive leap – that there was a third brother who held this role. Baring-Gould referred to this brother as ‘Sherrinford Holmes’, which was the name Arthur Conan Doyle almost gave to his famous detective.

It seems now then that Sherlock is set to introduce this third Holmes brother. In the previous season’s His Last Vow, Mycroft made reference to an unseen third brother, and at Comic Con writer Mark Gatiss teased an appearance by Sherrinford.

But it wouldn’t be out of character for Moffat and Gatiss to subvert expectations with their depiction of the third Holmes brother…

‘Toby isn’t the hacker’

Toby is a classic Holmes character (Picture: BBC)

Last night Sherlock got a new furry friend – but he’s actually one of the oldest characters in the Holmes canon, having been first introduced in the novel The Sign of Four.

Toby has been a popular character in different Holmes adaptations, ranging from novels that see Sherlock facing Dracula to the Robert Downey Jr movies.

Perhaps also appropriately, Toby appears in the animal adaptation The Great Mouse Detective, used by Basil as a means of transportation.

‘She’s like Napoleon now’

The Six Thatchers is a nod to classic Holmes story The Six Napoleons (Picture: BBC)

An offhand line of dialogue from Craig the hacker forms a reference to the iconic Arthur Conan Doyle story The Six Napoleons that this story is based on.



It’s not the only one, of course; there’s a very clever feint in the episode, as Sherlock believes that the Thatcher bust contains the black pearl, before it’s revealed that it the bust contains the AGRA USB.

This is another reference to the original story – where the Napoleon bust did contain the pearl – and a rather clever red herring for anyone who happened to be familiar with the original.

It’s not the only reference to Conan Doyle stories, of course; while multitasking, Sherlock mentions ‘the wrong thumb’, which could be assumed to refer to The Engineer’s Thumb, while ‘the Merchant of Sumatra’ is a reference to Conan Doyle’s The Giant Rat of Sumatra.

There’s also Sherlock’s request of Mrs Hudson that she whisper “Norbury” to him, should he ever appear to be getting too arrogant; it’s a request that Doyle’s Holmes made of Watson in The Adventure of the Yellow Face, one of the few stories in which Holmes deductions proved incorrect.

Of course, the mistake Sherlock made in The Six Thatchers is far greater than a simple mistaken deduction, and will no doubt prove to have far-reaching consequences for the rest of this series…

Alex Moreland is a freelance writer and student based in London. You can read more of his work here.

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