In Alfred Hitchcock’s playful thriller, Verloc, a London cinema owner, works with a group of terrorists to wreck havoc in the capital. His wife (American actor Sylvia Sidney) begins to suspect he is involved in sabotage, but it is her brother who becomes directly involved, when Verloc asks him to transport a package to Piccadilly Circus, which, unbeknownst to the boy, contains explosives. This leads to one of the tensest sequences in a Hitchcock film.
The film was adapted from The Secret Agent by Joseph Conrad, not to be confused with Hitchcock’s previous feature, which shared the book’s title. The set pieces, from London being plunged into darkness at the start to a key moment of tension involving a carving knife near the end, are among the best from Hitchcock’s British films.