Sian Brooke: 'To find out Eurus is Sherlock’s sister was incredible and magical!'

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Sherlock’s sister Eurus revealed her true identity at the end of the last Sherlock episode and actress Sian Brooke revealed the lengths she went to to keep it quiet...

There was another shock cliffhanger in the latest Sherlock mystery as Sherlock’s sister Eurus unmasked herself.

The sly sibling had already appeared in the previous two episodes, but heavily disguised as three different women – bus passenger Elizabeth or ‘E’, who had the hots for Watson; Faith, the ‘Lady in Red’ who visited Sherlock late at night saying she was the daughter of megalomaniac businessman Culverton Smith (Toby Jones); and Watson’s German therapist Elsa who then shot him in this latest dramatic cliffhanger.

“I couldn’t quite believe it when I read about my character shooting John Watson. That incident was my first day of filming too!" reveals Sian Brooke, the actress who plays mysterious Eurus.

"As she’s had a flirty affair with John Watson and shoots him, I’m not sure how Sherlock fans are going to react to her! They might not like her very much!

“I’ve been a fan of the show from the beginning. I just think it’s genius. I’ve loved watching it, so to be a part of it was truly magical. And also to be playing so many different roles – these opportunities come along so rarely. It’s quite a relief to be able to talk about Eurus now to be honest. It’s all be very strange, because I’ve had to keep it secret for 7 or 8 months, and I’ve not been able to tell anyone even my family.

“Keeping things secret was so tricky… I was in Cardiff filming for three months, and my neighbours kept wondering where I kept going off to because I’ve got two kids. I just had to tell them I was filming a crime drama for the BBC that starred no one they’d know, all new faces!”

“Trying not to be seen while filming was tough, especially walking around London as Faith in a red dress when the paparazzi were around.

"At that point I hadn’t even told my family. The picture got in some local paper in Wales, and I have Welsh family and my uncle rang up to ask what I was doing on the front of a newspaper with Benedict Cumberbatch. I just said I was out for the day and covered it!”

The last episode of the series - The Final Problem - sees Eurus again in the thick of the action, and it will be revealed if Watson (Martin Freeman) has survived the gunshot. Viewers will also see if Eurus has a big confrontation with her brothers Mycroft (Mark Gatiss) and Sherlock (Benedict Cumberbatch).

"It was incredible and magical when I first found out Eurus and Sherlock were brother and sister," said Sian, who worked with Benedict, playing Ophelia in a stage prodcution of Hamlet. "I’ve loved the show for such a long time so to now be Sherlock’s sister is amazing. Even when I was given the part, I still didn’t know exactly who she was – or even that she was related to Sherlock. I read that bit of the script when I was at a playgroup with my kids, trying to stifle my excitement!

“There’s more of Eurus in episode three, but you never know with Sherlock where the story will go…"

Steven Moffat, who created the series with Mycroft actor Mark Gatiss, added: “We introduced Sherlock’s mum and dad a while ago, almost on a whim. Now we’ve just taken a few more steps along that line. People had posited a brother, but we thought maybe we could have a sister.

"Sian’s an absolute gem, and her performance in the final episode is astonishing and terrifying. It was tough to cast because we wanted someone who absolutely should be a star but isn’t, like Benedict Cumberbatch was before series one.”

Eurus represents the dark side of Sherlock, which is usually suppressed by the warmth of John’s friendship. "We often think about what Sherlock would be like if he hadn’t been rescued by Watson. How would that have ended up?" said Steven.

"But we didn’t introduce Eurus for a deep, thematic reason, we’re also just trying to have fun with proper surprises.

“Experiments show that people don’t really record faces very quickly and the characters do not look alike," said Steven. "I stuck in a couple of distractions that kept drawing your eye away, like the walking cane.”

The latest episode ended with Eurus pulling a gun on Watson and then the trigger. But surely it’s a step too far to kill off Sherlock’s right-hand man?

"Who am I to tell you what to deduce? I promise it’s more fun if you don’t know," grinned Steven.

“There’s been a lot of talk about this series being the last run, but it’s all made up! People are taking quotes out of context, we’ve never said that at all.

“Everybody would like to do more, but it’s a nightmare to schedule," added co-creator Mark. "We’ve filmed Sherlock and John meeting for the first time as young men so we’d love to carry on until they’re the age of Basil Rathbone and Nigel Bruce in their films.”

*Sherlock: The Final Problem will be shown on BBC1, Sunday January 15 at 9pm

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Nicholas Cannon
TV Content Director on TV Times, What's On TV and TV & Satellite Week

I'm a huge fan of television so I really have found the perfect job, as I've been writing about TV shows, films and interviewing major television, film and sports stars for over 25 years. I'm currently TV Content Director on What's On TV, TV Times, TV and Satellite Week magazines plus I previously worked on Woman and Woman's Own in the 1990s. Outside of work I swim every morning, support Charlton Athletic football club and get nostalgic about TV shows Cagney & Lacey, I Claudius, Dallas and Tenko. I'm totally on top of everything good coming up too.