“We wanted to do something lavish,” says executive producer Nicholas Briggs. “The Worlds of Doctor Who will be published in similar packaging to the acclaimed Special Edition of our fiftieth anniversary story The Light at the End. That means not only a fantastic story full of lots of familiar friends, but also a glorious book of behind the scenes information and special photography.”

The five-disc release will encompass many of Big Finish’s Doctor Who ranges, while telling one huge interlinking story. It begins with Mind Games, in which Henry Gordon Jago (Christopher Benjamin) and Professor Litefoot (Trevor Baxter) investigate a sinister stage magician who is working at Jago’s theatre in Victorian London. That magician, Mr Rees, will make his presence felt throughout these adventures, and he is played by none other than Jamie Glover, who portrayed William Russell in An Adventure in Space and Time.

The story shifts to the early 1960s in The Reesinger Process, as Rachel Jensen (Pamela Salem), Group Captain Gilmore (Simon Williams), Allison Williams (Karen Gledhill) and Sir Toby Kinsella (Hugh Ross) set Counter-Measures in motion when a number of high profile public figures die in strange circumstances.

A few decades later, the UNIT vault is in lockdown in The Screaming Skull, and Mike Yates (Richard Franklin) brings operatives Ruth Matheson (Daphne Ashbrook) and Charlie Sato (Yee Jee Tso) out of isolation in order to break inside.

Finally, in Second Sight, the Sixth Doctor (Colin Baker) is on the scene – and so are agents from Gallifrey, in the form of Romana (Lalla Ward) and Leela (Louise Jameson). And the final battle with Rees commences…

“I’d had the central idea for The Worlds of Doctor Who some time ago,” says producer David Richardson, “but – as is often the case – it was held in suspended animation until the time was right to do it. And it seems fitting that this collaboration between the Doctor and many of his friends should mark our anniversary. This story has been quite a party to make, and I hope listeners will throw themselves into the celebrations too.”

The scriptwriters are Justin Richards, Jonathan Morris and Nick Wallace, and the directors are Ken Bentley and Lisa Bowerman.

The Worlds of Doctor Who is now available for pre-order on CD and download.