As range producer Ian Atkins explains: 'We're always wary about announcing details of things that definitely haven't happened yet, or which might move in release order, so the Short Trips announcements tend to be for the next few titles. But when a story is specifically a Christmas one, it clearly isn't going to move! And we have the two of them recorded now, so...'

December 2016's story is Doctor Who: The Hesitation Deviation by James Goss, read by Lisa Bowerman as Professor Bernice Summerfield as she travels with the Seventh Doctor.

'I asked James for something Christmassy,' says Ian, 'and what he's delivered both warms the heart and chills the marrow. It gives your internal organs a full work-out!'

'The Hesitation Deviation is a Christmas story' says James. 'Or rather, proof that, even on a planet that loves Christmas, the Doctor can't have a good time, no matter how hard he tries. Christmas is a time for remembering, but for Benny it becomes a time for forgetting. Hopefully it's a little creepy. But also Christmas is the one time that the Doctor's jumper doesn't stand out.

The 2017 Christmas title – and the last in the current run of Doctor Who Short Trips – is Anthony Keetch's Doctor Who: O Tannenbaum, performed by Peter Purves.

Says Ian, 'Lisa Bowerman recommended Anthony as a writer when we were building our list of contributors last year, and after some conversations with him we agreed on a storyline for the Doctor and Steven, with Peter Purves reading it so very evocatively. It was a real pleasure to watch him work.'

'I wanted my Short Trip to have the feel of an old annual story,' explains Anthony. 'Recognisably Doctor Who, but slightly off-kilter, the sort of thing you wouldn’t see on the telly. A bit spooky, like the ghost stories we’re told people used to tell each other at Christmas (although I’ve never actually experienced that - someone come around and tell me one).'

Both Doctor Who: The Hesitation Deviation and Doctor Who: O Tannenbaum are available to pre-order for £2.99 each, or they come as one of the 12 titles in each year's value-for-money Doctor Who – Short Trips Subscription. A bundle for the 2015 releases is also available.