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Who plays Sherlock's Eurus Holmes?

Meet actor Siân Brooke, who played a surprising role in the latest episode of the BBC detective drama – and has some history with Benedict Cumberbatch (contains spoilers)

Published: Wednesday, 18th January 2017 at 12:03 pm

Tonight’s episode of Sherlock ended with a shocking twist, as it was revealed that Sherlock and Mycroft Holmes’ long-rumoured secret brother was actually their sister, and that she’d been appearing throughout the episode in disguise the whole time.


Anyway, in case you were wondering the person behind the various outfits (and evil plans) was actor Siân Brooke – and this is everything you need to know about the newest addition to the Sherlock family.

Getting started

Born in Lichfield, Staffordshire to Welsh parents, Brooke is the youngest of three siblings and began her acting journey as a member of the National Youth Theatre before training at RADA (the Royal Academy of Dramatic Art) and graduating in 2002.

Notably, Brooke’s real surname is actually Phillips, but she changed her stage name to avoid confusion with Welsh actress Siân Phillips. Her new surname, Brooke, was apparently taken from an English Civil War general who served at her home town.

TV career


Brooke in Channel 4's Not Safe for Work

Brooke’s first credited role was in 2003 Disney series Dinotopia, with roles following in Rik Mayall comedy All About George, crime dramas like A Touch of Frost and Foyle’s War and TV movies like Housewife, 49 and Under the Greenwood Tree.

Later, in 2007 she landed the recurring role of Lori in David Morrissey-starring drama Cape Wrath, where she acted alongside future movie stars Felicity Jones, Tom Hardy, Sean Harris and Harry Treadaway.

Over the years guest roles in Doc Martin, Vexed, New Tricks, Silk, Garrow’s Law, Lewis and Man Down beckoned, with Brooke recently appearing as Martine in Channel 4 comedy Not Safe for Work and as Natalie in The Moorside Project.



Brooke has had a long stage career, appearing in the likes of A Midsummer Night’s Dream, King Lear and Romeo and Juliet with the Royal Shakespeare Company and playing Dorothy in the Wizard of Oz at London’s Southbank centre. She has also appeared in Stephen Poliakoff’s My City and Neil LaBute’s Reasons to be Pretty.

However, of most interest to Sherlock fans will be one of her more recent stage roles, where she played Ophelia in the Barbican production of Hamlet alongside future Sherlock co-star Benedict Cumberbatch (who played the title role).

Why she was cast


Brooke in last week's Sherlock episode

Speaking about their decision to case Brooke as the third Sherlock sibling, series co-creator Mark Gatiss said:

"Obviously this was a huge thing to cast Siân, as Eurus, this unknown sibling, and what we asked…the casting director to do, was essentially find someone that she thought should already be a big star. Who’s never quite got the break.

"And we saw a few people but Siân was just wonderful and absolutely knocked it out of the park.

“Wait ‘til you see her next week,” co-creator Steven Moffat added. “Next week is amazing.”

We imagine the fans will do just that.

Sherlock continues on BBC1 next Sunday (15th January) at 9.00pm


Sherlock series 4 episode 2 reviewed


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