Talk about keeping it in the family! Sherlock co-creator Steven Moffat had already enlisted his wife Sue Vertue to produce the detective drama. Then, in the first episode of series three, he called on Benedict Cumberbatch’s real-life parents to play Sherlock’s mum and dad. But for tonight’s finale he went one better, handing his own son the title role.


When Sherlock retreated to his Mind Palace after receiving a potentially fatal gunshot wound, Louis Moffat – Steven and Sue’s son – appeared as his younger self, complete with the luxuriant curls that are both the detective’s trademark as well as a trait inherited from Moffat’s side of the family.

In the scene, young Sherlock is seen beckoning to the one thing that can calm him down and prevent him going into shock after being shot: his beloved boyhood dog Redbeard.

That in itself was something of a revelation for fans, who had been puzzling over the identity of the mysterious “Redbeard” after the name was mentioned in passing by Sherlock’s brother Mycroft. “I’m not a child any more,” was Sherlock’s response at the time, but it seems that sometimes even the terminally aloof detective needs to get back in touch with his inner child…

Moffat said delving into Sherlock’s past was a logical next step in bringing Sir Arthur Conan Doyle’s creation up to date.

“Thirtysomethings in the modern world are still in touch with their parents,” said Moffat, “and once we’d got the parents in, and you’ve got the sibling rivalry [with Mycroft], you start to think ‘Well, what was the young Sherlock like?’ You just want to see those things, it’s part of updating it.”

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