By Joseph Lidster.

The Torchwood team go to Geneva, where former time-traveller Martha Jones is now working as a doctor at the world's biggest physics laboratory, CERN. Deep in an underground tunnel, a giant particle accelerator is about to be activated for the first time. But something strange is happening. Scientists are hearing voices and collapsing with a strange illness. Is something lurking in the tunnel? Do the dead ever really stay dead?

Captain Jack Harkness ...... John Barrowman
Gwen Cooper ...... Eve Myles
Ianto Jones ...... Gareth David-Lloyd
Martha Jones ...... Freema Agyeman
Professor Johnson ...... Lucy Montgomery
Dr Oliver Harrington ...... Stephen Crichlow
Leon Foiret ...... Mark Meadows

Music by Murray Gold and Ben Foster.

Directed by Kate McAll. Show less