Released: Thursday 30th June 2011
9:00pm BST (20:00 GMT) < > « »  < > « »
Big Finish Release

Featuring: Peter Davison, Janet Fielding, Mark Strickson, Sarah Sutton

1983: as the country goes to the polls, two ‘Urban Explorers’, together with a freelance journalist, break into the long-defunct Cadogan Tunnels, once a secret wartime facility… and later, so rumour has it, the site of an experimental laboratory with a nasty sideline in vivisection.

What they find, in its twisting underground corridors, is something the most cynical conspiracy theorist could never have imagined: a highly-evolved society of questing, intelligent creatures, living right under humanity’s nose for decades.

But there’s no way out of the tunnels – as the Doctor, Nyssa, Tegan and Turlough are about to discover when the TARDIS brings them, too, into the complex. It’s a rat trap – and they’ve all been caught!
Synopsis Source: Doctor Who Guide