London Below is slowly coming to life. With less than two weeks to go until Radio 4/4 Extra opens a portal to the magical realm in fantasy drama Neverwhere, we have a gallery of exclusive shots of the star-studded cast, including Benedict Cumberbatch, James McAvoy and Natalie Dormer.

McAvoy is Richard Mayhew, a young businessman drawn into the subterranean world of London Below after he comes to the aid of a girl named Door, played by Dormer. In a place where famous landmarks take on a life of their own, Benedict Cumberbatch is the Angel Islington, an actual angel who watches over the city beneath the city.

James McAvoy in Neverwhere teaser trailer: "I'm not going mad. Am I?"

David Harewood plays trickster the Marquis de Carabas, with Bernard Cribbins as his friend (and debtor) Old Bailey, and Christopher Lee as the Earl of Earl's Court. Sophie Okonedo is legendary bodyguard Hunter.

Dirk Maggs' six-part adaptation of the original story by Neil Gaiman begins with an hour-long episode at 2:30pm on Saturday 16 March on Radio 4 and continues with five 30-minute instalments across the week at 6pm on Radio 4 Extra from Monday 18 March.

For more on Neverwhere – including clips read by its stars, commentary by Neil Gaiman and an in-depth guide to the characters – visit the official Radio 4/4 Extra Neverwhere site