Starring the 1980s TARDIS team of Peter Davison, Janet Fielding, Sarah Sutton and Mark Strickson, Doctor Who: Heroes of Sontar is written by Alan Barnes, directed by Ken Bentley, and also features John Banks, Duncan Wisbey, Alex Lowe, Derek Carlyle and Andrew Fettes.

Planet Samur was once a peaceful haven. Pilgrims journeyed across the seven galaxies to meditate in the courtyards of the vast Citadel that spanned its equator. It was Samur’s misfortune, however, to find itself situated on the furthermost frontier in the eternal war between the amoeboid Rutan Host and the belligerent, troll-like Sontarans…

Twenty years after detonating a bacteriological weapon over Samur, rendering it uninhabitable, the Sontarans are back: a select platoon of seven has landed here on a secret mission, carrying sealed orders given to them by Fleet Marshal Stabb.

The TARDIS has landed here, too, bringing the Doctor, Tegan, Turlough and Nyssa into the second great Battle of Samur. Fighting not only the Sontarans, but mystical mercenaries… and a deadly, decades-old curse.

For this month only, Doctor Who: Heroes of Sontar is available for £2.99 on download and we'd like to hear what you made/make of it! You can chat about the story on the forums or on our Big Finish Facebook page, and you can learn more about it in this month's Listen Again in the new issue of our free downloadable magazine, Vortex.