Who is Susan Twist's character in Doctor Who? All the theories

Plus, she's set to appear in the next episode, 73 Yards, as a hiker, and we most recently found out that she'll be playing a character named Penny Pepper-Bean in episode 5, Dot and Bubble. It could be the star's biggest role yet, as it's clearly linked to a major guest star for the episode, Callie Cooke's Lindy Pepper-Bean.

While it's not out of the ordinary for actors to play different roles in the show, it's definitely unusual for it to happen this quickly and this much – leading fans to wonder if there's more to her than meets the eye.

Actress Twist recently addressed her recurring roles, telling Doctor Who Magazine: "It’s so nice to be these different people and have all those different looks. It’s very clever. ‘Ooh, it’s that woman again."

So, who could Susan Twist's character be? Fans have plenty of theories.

Who is Susan Twist's character in Doctor Who?

So, first of all Twist cropped up in the opening scenes of Wild Blue Yonder as a maid accompanying Isaac Newton (played by Nathaniel Curtis). She was only seen briefly in the episode but the character was named Mrs Merridew.

Next, fans noticed Twist at the concert played by Ruby's band in The Church on Ruby Road. This time she was playing an unnamed character who made a request of the band: "Can you do Gaudete?"

Gaudete, which means 'Rejoice Ye' in Latin, is a Christmas carol thought to have been composed in the 16th century. We're not sure if this will have any bearing in the show's future but, when it comes to showrunner Davies, nothing can be overlooked!

Twist appeared again – uncredited – in season 14 episode 1, Space Babies, as one of the humans who abandoned the space station orbiting the planet Pacifico Del Rio.

We see a brief snippet of a recording of Twist as "Comms Officer Gina Scalzi", who – like the rest of the crew – is signing off and leave the space babies to their fate in the year 21506 - making it clear how far into the future her appearances range.

In season 14 episode 2, The Devil's Chord, Twist is credited simply as 'Tea Lady' – she appears in the canteen of the EMI Recording Studios, charging the Doctor and Ruby half a crown for two cups of tea. When the Doctor refers to the price as "daylight robbery", the tea lady responds: "That’s me, Margaret Lockwood, in The Wicked Lady. Now there was a woman – statuesque."

Of course, Twist appeared once again in perhaps her most prominent role yet, as the Ambulance in Steven Moffat's Boom, an AI system from weapons manufacturer Villengard.

Meanwhile, we now know who she'll be playing in 73 Yards, as she's on the cast list as 'Hiker'. Plus, she'll appear in the Black Mirror inspired next episode, Dot and Bubble, as Penny Pepper-Bean.

Doctor Who Magazine has also revealed that Twist will have a starring role in the finale two-parter, The Legend of Ruby Sunday and Empire of Death – so could this be when her character's identity comes to light?

While she doesn't appear in the cast list for any upcoming episodes (even though she's got cameos in at least one of them, and presumably more), she's listed among the actors 'starring' in the finale episodes in the magazine's previews. Something tells us we could be getting some answers very soon.

Showrunner Russell T Davies has only addressed Twist's continued appearance by joking about there being a "shortage of actors" at actors' union Equity and, quite simply, no one believes him!

Some fans think Twist's character will have something to do with Triad Technology, a company name that was spotted on set when season 14 was filming.

Some are convinced they saw the name Susan Triad on a poster of Twist in Russell T Davies's office during an interview he gave during Imagine... Russell T Davies: The Doctor and Me. Could she be a new villain – perhaps a tech mogul or a politician?

Twist has also appeared across various different times – could she be another time traveller following the Doctor?

One new theory is that twist is actually playing a TARDIS. If she is in fact playing a character named Triad, with the first initial S, that would be an anagram of TARDIS.

Of course, nothing is confirmed yet and only time will tell

There are other mysteries that still haven't been solved from the 60th anniversary episodes and the Christmas special too. Maybe Twist's character has something to do with Ruby's birth mother – or she's the Meep's boss, who was referenced in The Star Beast.

Could she have something to do with the woman who picked up the gold tooth that trapped the Master in The Giggle?

Fingers crossed we'll find out more soon!

All of Susan Twist's roles in Doctor Who so far

• Mrs Merridew – Wild Blue Yonder
• Unnamed character at concert – The Church on Ruby Road
• Comms Officer Gina – Space Babies
• Tea Lady – The Devil's Chord
• Ambulance – Boom
• Hiker – 73 Yards
• Penny Pepper-Bean – Dot and Bubble

Who is actress Susan Twist?

Susan Twist has had various roles across TV, radio, and stage. Early in her career, she was known for appearing in various episodes of Brookside, and she's since appeared in Doctors, In the Flesh, Coronation Street and The Archers.

As for her stage career, she's appeared in productions like The Three Musketeers, Prize Night, Jack Flash and Taming of the Shrew.

Doctor Who continues on Saturday 25th May on BBC iPlayer and BBC One. Previous seasons are available to stream on BBC iPlayer.

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