Doctor Who filming a sequel to 'Planet of Fire' next week?

Doctor Who filming a sequel to 'Planet of Fire' next week?

Here's some interesting Doctor Who news. The BBC recently announced that actress Hermione Norris will be guest starring in an upcoming episode written by Wallander scriptwriter, Peter Harness. Also featuring in the episode are Ellis George (who according to BlogtorWho plays Danny Pink's teenage sister), Phil Nice, and Tony Osoba (who played the Movellan Lan in Destiny of the Daleks).

More interesting though, is this blurb from Stephen Moffat: For the first time since 1984, the Doctor Who production team is heading to Lanzarote. The Doctor is returning to the scene of an old adventure - but there have been sinister changes since his last visit.'

The 1984 episode in question was Planet of Fire, and Lanzarote doubled as both itself and the volcanic planet Sarn. Unless the 12th Doctor is on a quest to prevent Turlough from running around in tiny pants, it seems more than likely that we can expect a return to the former Trion prison planet, rather than the Spanish vacation spot.

Interestingly enough, the last time the Doctor visited Sarn, it was to stop the Master from using the planet's unique regenerative gas to restore himself to regular size after accidentally shrinking himself to the size of a Mego doll with his own TCE (this was during the phase in the Master's career where he became less of a cosmic threat, and more of a danger to himself and others.) And a couple of months ago, Sylvester McCoy may have inadvertently let slip during a Comic Con interview that he knew who would be playing the new Master, and he would be "very scary."

I rather like the idea of Capaldi's Doctor squaring off against a suaver, more Roger Delgado-like Master, free of Russell T. Davies god-awful "drums," but I also can't really picture anyone doing a straight-up sequel to Planet of Fire, as there's not much of a tale left there to tell... at least not without visiting Trion.

I figure it's far more likely that Harness wrote an interesting volcano planet story, and Moffat, being a pragmatist and a classic Who fan, simply reasoned "if we're going to be shooting in the same locations, why not set it on the same planet?"

Doctor Who filming a sequel to 'Planet of Fire' next week?

EDIT: And now we have confirmation that filming in Lanzarote begins next week. Which considering that we're a week into Block Four, likely means that they're shooting interiors this week, and next week will be mainly exteriors.

EDIT x2: Some more grist for the rumor mill. It's vaguely possible this story is called either Flatline or Kill The Moon as it certainly isn't Mummy on the Orient Express, though I'd hazard a guess that "none of the above" is far more likely.