Released today, Doctor Who - Absolute Power and Doctor Who - Quicksilver see Colin Baker and Miranda Raison conclude a trilogy of stories as The Doctor and Mrs Constance Clark after last month's Doctor Who - Order of the Daleks.

Written and directed by Jamie Anderson, son of children's TV legend Gerry, Absolute Power sees the travellers arrive on an alien world with a terrifying history:

Two thousand years ago, all civilisation on the planet Teymah was wiped out in an AELE – an Anomalous Extinction Level Event. Now, the galactic entrepreneur Lyam Yce hopes, at last, to learn the reason why the ancient Teymahrians went extinct – by funding a huge archaeological dig. While the Doctor probes a strange sphere found by Yce's diggers, his companion, former Bletchley Park cryptographer Constance Clarke, agrees to help translate symbols written in the lost ancient language of the Teymahrians. And soon, they'll learn that ancient Teymah's secrets were best left buried deep beneath its shifting sands...

Doctor Who - Quicksilver, written by Matt Fitton, brings Mrs Clark home to Earth where the Doctor is about to unexpectedly encounter a familiar face:

It’s the telegram Constance never wanted to read:

 DEEPLY REGRET TO INFORM YOU LT-CMDR H CLARKE LOST IN ACTION. CLASSIFIED OPERATIONS. 

Those classified operations concerned a top-secret military project code-named ‘Quicksilver’. A project based in Vienna. A project with alien connections.

But bombed-out Vienna is not what it was before the war – with its Strauss music, its glamour and easy charm. It's not the time nor the place for a happy reunion. As Constance Clarke is about to discover...

And as the Doctor is about to discover, too!

Doctor Who - Absolute Power and Doctor Who - Quicksilver can be bought for £12.99 on Download and £14.99 on CD each, or as part of a six- or 12-story Subscription.

Subscribers not only get reduced prices, but also access to scripts on PDF, an extended extras download, and a brand new Doctor Who - Subscriber Short Trip every three months. For December this is Third Doctor story Doctor Who - The Christmas Dimension written by Rob Nisbet and read by Stephen Critchlow.

All CD purchases unlock access to a free digital version. If you have an iOS or Android device, use the free Big Finish app to listen on the go!

Big Finish's main Doctor Who range continues in January when Peter Davison's Fifth Doctor encounters The Star Men...