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

Plus, we now know exactly who the actress will be playing in the finale two-parter: a character named Susan Triad. It's a name fans have seen before, and it seems we might be getting some answers very soon.

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."

Twist appeared once again in Boom as the Ambulance in Steven Moffat's episode, an AI system from weapons manufacturer Villengard.

She then appeared as a hiker in 73 Yards, running into Ruby on the clifftop. She appeared confused as to why Ruby wanted to send a message to the woman, but did as she asked.

When Twist's character approached the woman, she ran away scared at whatever the woman said to her. Ruby briefly questioned if the pair had met before, but quickly brushed off the thought.

But in Dot and Bubble, there was a marked shift, with both the Doctor and Ruby now cottoning on to the fact that there's something amiss with Twist's character (as we mentioned, Ruby did recognise her as the hiker in 73 Yards, but that event was later erased).

In Dot and Bubble, the mysterious returnee appeared as Penny Pepper-Bean, who is 62 years old and has 3,108 subscribers in her friendship circle.

Her daughter, Lindy Pepper-Bean (Callie Cooke), was trapped in the monster-infested residence of Finetime and with the help of the Time Lord and his companion, they were able to guide Lindy to safety using a "dot and bubble" communications system.

"I've seen her before," said Ruby, with the Doctor drawing a connection between the character and "the face of the ambulance on Kastarion 3" in Boom.

"No no no, I've seen her somewhere else," said Ruby, but with Lindy still in danger at that point, the pair had to abandon their discussion for another time.

It's also important to note that Twist's role in Dot and Bubble is the first time she's played someone with familial ties to another character in an episode – which could mean she isn't just one character wearing a plethora of disguises, but several different people who all look the same, recalling the 2005 episode Bad Wolf.

Next, Twist will play a portrait in Rogue, which stars Jonathan Groff and Indira Varma alongside Gatwa and Gibson.

Plus, in the finale, it's been confirmed that Twist will play a character called Susan Triad. . The name might not be new to some fans, after eagle-eyed viewers spotted a poster with that name in Russell T Davies's office in the programme Imagine... Russell T Davies.

Some fans have theorised that Twist is actually playing a TARDIS, due to S Triad being an anagram of TARDIS. However, the full extent of Twist's role in the finale is yet to be revealed.

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.

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. Considering she is 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
• Portrait – Rogue

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 1st June on BBC iPlayer and BBC One. Previous seasons are available to stream on BBC iPlayer.

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