The forthcoming seventh season of Doctor Who, currently in production in and around South Wales and at the BBC’s impressive new Roath Lock studio complex, is shaping up to be the most star-studded season since the show’s revival in 2005. Episodes filmed so far have already boasted an impressive roll call of talent such as Mark Williams, Ben Browder, Rupert Graves, David Bradley, Jemma Redgrave, Steven Berkoff and just last week the BBC announced the recent participation of Liam Cunningham and David Warner. However today the show has announced one of its biggest-ever casting coups as the legendary Dame Diana Rigg (forever remembered at catsuit-wearing Emma Peel in the 1960s classic TV adventure series The Avengers… no, not the one with Iron Man and the Hulk!) and her actress daughter Rachael Stirling step aboard the TARDIS (metaphorically) in an episode written by long-time writer/fan Mark Gatiss currently being filmed in the picturesque village of Bute Town in the Rhymney Valley. The episode will see Rigg and Stirling as “a mother and daughter with a dark secret” as they meet up with the Doctor (Matt Smith) and his new assistant (Jenna Louise Coleman).

Gatiss’ episode is rumoured to be set in the past, in a remote Yorkshire village where, it seems likely, something mysterious will happen. Rachael Stirling, appearing on screen with her mother for the first time, describes the episode as “a gift of a script” and the show’s executive producer Steven Moffat says “Dame Diana Rigg, Rachael Stirling and a Mark Gatiss script – a combination of talents you could only get in Doctor Who. Frankly, I’m terrified already.”

We’ve a bit of a wait for this tantalising episode which won’t be screened until the second half of season seven in early 2013.

Doctor Who is expected to return to UK screens at the end of August.

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