Warning: Spoilers ahead for Doctor Who season 14 episode 3, Boom.


After Varada Sethu made a shock appearance in Doctor Who's new episode Boom, a whole year earlier than she was initially expected, writer Steven Moffat has teased that there's "a plan" in place for her character.

This year, it was confirmed that Sethu will join the cast of season 15 as a new companion - but no one expected her to arrive this early, as new character Mundy Flynn in Moffat's episode Boom.

Teasing what's ahead, Moffat said: "There is a plan. That’s all I’m telling."

Varada Sethu, Ncuti Gatwa and Millie Gibson at a Doctor Who table read
Varada Sethu, Ncuti Gatwa and Millie Gibson at a Doctor Who table read BBC

Referencing how Jenna Coleman's Clara initially appeared in an episode long before she made her return as a companion, he added to The Hollywood Reporter: "I mean, I was talking to Russell [T Davies, showrunner] about what we’re going to do, but she’s there! We’re just going to do Clara again. So it’s fun, isn’t it? It wakes you up. You think, “Ah, there she is!”"

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Asked about the significance of the character's name, Mundy (similar to "Monday"), he added: "And I think I’m going to say nothing about that. I’m going to say nothing about what’s going on there. You’re not going to get nothing. It’s Russell’s plan and he will release the details of how that works in his own time, I’m certain."

Davies is also keeping tight-lipped, saying on Doctor Who: Unleashed: "She's coming in into season 2 but quite how that happens, what happens, why it happens, is very much knitted into the story of the Doctor and the story of Ruby Sunday."

Steven Moffat standing on the set of Doctor Who episode Boom, with a fiery and smoky backdrop of rubble, and actors and crew members out of focus behind him. He has a pair of headphones around his neck and is smiling at the camera.
Steven Moffat standing on the set of Doctor Who episode Boom. BBC Studios/James Pardon

However, Sethu has confirmed that she only found out she'd been cast as a full-time companion "months" after she wrapped filming on Boom.

She said on Doctor Who: Unleashed: "I was just in it for the ride, I had a great time for those three weeks. I was devastated to be leaving because I had so much fun but I didn't know anything about it. That call came much later, months and months later."

Moffat returned after seven years to write Boom, the former showrunner also recently revealing he penned the 2024 Christmas episode Joy to the World.

But will he have more to do with Sethu's character after introducing her to the Whoniverse? It may be unconnected, but he did recently reveal he's read the season 15 finale script "for reasons that will become apparent". Make what you will of that!

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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