David Suchet and Peter Capaldi star in this three-part BBC adaptation of Joseph Conrad's novel. Adolf Verloc (Suchet) is a Russian spy living as a shopkeeper in Victorian London with his wife, Winnie (Cheryl Campbell), and her mentally handicapped brother, Stevie (Richard Stirling). When Verloc's Russian superiors order him to blow up the Greenwich Observatory in an act of terrorism, Verloc persuades Stevie to assist him. However, Stevie trips and explodes the bomb in Greenwich Park, killing himself and putting Chief Inspector Heat (Warren Clarke) of Scotland Yard on Verloc's trail.