The subterranean environs of London Below are brought to life in a new clip from the Radio 4/4 Extra adaptation of Neil Gaiman's Neverwhere. Benedict Cumberbatch – as the enigmatic angel, Islington – half sings, half whispers some haunting verses as he stalks the echoing confines of his underground domain.
For an extra-eerie effect, open this page in two (or more) windows and start the clip playing for a second time, say 15/20 seconds after the first one has started (the more windows you open, the weirder it gets...)
Neverwhere is the tale of London Below, a magical realm beneath the capital where famous landmarks take on a life of their own.
The star-studded dramatisation, also featuring James McAvoy, Natalie Dormer and Christopher Lee, begins at 2:30pm on Saturday 16 March with an hour-long episode on Radio 4 and continues with five 30-minute instalments at 6pm, Monday to Friday, on Radio 4 Extra from 18 March.