Doctor Who boss offers ominous warning about character in Steven Moffat's Boom

Now, while speaking on The Official Doctor Who Podcast for episodes 1 and 2, Space Babies and The Devil's Chord, showrunner Russell T Davies has teased what fans can expect from the episode, and offered up hints towards the wider plot and supporting characters.

"We're on war-torn planet Kastarion 3," he explained. "It's bleak, it's scary, it's muddy, it's foggy, it's dangerous, and that throws Ncuti's Doctor into the most extraordinary situation in which both he and Ruby have to act at the height of their powers and use all their wits to escape from this.

"There's a great supporting cast and there's a great supporting character called Splice, and one thing I would say in this story is be very careful about saying Splice's father's name out loud."

Splice is being played in the episode by Caoilinn Springall, who has previously had roles in The Midnight Sky, Citadel and Stopmotion – however, beyond that we know very little about the character or how Davies's warning will play out.

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Davies previously hyped up Moffat's new episode at a recent Q&A, saying that "people will be talking about that for years to come".

He explained: "At the very start of that, the Doctor stands on a landmine and can't move for the entire episode – that is absolutely a masterpiece of performance from [Ncuti and Millie], and in terms of tension, it's just incredible."

Meanwhile, Moffat himself has said that he thought the concept for the episode was "dynamite", adding that Davies emailed him back after he pitched it saying: "That’s it, go write that, I want that immediately."

He continued: "It’s a collaboration of enthusiasm… what we’re doing is giggling and laughing and shouting and bounding around the room about how clever and exciting all this is.

"If you're not doing that on a show like Doctor Who – or, frankly, any show – what's the point?"

Doctor Who continues on Saturday 18th May on BBC iPlayer and BBC One. Previous seasons are available to stream on BBC iPlayer with episodes of the classic series also available on BritBox – you can sign up for a 7-day free trial here.

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