Before Missy was even a mad gleam in the eye of actor Michelle Gomez, she was in a Big Finish recording booth opposite Sylvester McCoy's Seventh Doctor as Jevvan in Doctor Who - Valhalla. For this special offer weekend, you can buy this title now for £5 on Download or £6.00 on CD.

Doctor Who - And You Will Obey Me, written by Alan Barnes and starring Peter Davison and Geoffrey Beevers kicked off last year's hugely-regarded Master trilogy - an epic battle between Time Lords across three main Doctor Who range adventures. The second tale Vampire of the Mind by Justin Richards (starring Colin Baker and Alex Macqueen) and The Two Masters by John Dorney (starring Sylvester McCoy, Geoffrey Beevers and Alex Macqueen) concluded the saga.

Until mid-day on Monday (UK time) these three stories can each be bought for £6.50 on Download or £7.50 on CD. Doctor Who - Week 10 Bundles have been set up for those wanting to buy all four releases in one go.

If you're an Apple or Android device user, don't forget to use the free Big Finish Listening app - especially useful for those waiting for CD orders to arrive, as they can listen to the digital version their purchase has unlocked exclusive to Big Finish.