The film stars Philippe Hersent as Landers (code name North Pole), a British radio operator and cryptographer captured in occupied Holland.
Under the watchful eye of Colonel Bernes (Curd Jurgens) and other Nazi officials he is forced to send false and misleading radio messages to London in an attempt to undermine British intelligence.
[2] Meanwhile, in Britain Lt Mary Wintergreen, a pretty female officer (Dawn Addams), says goodbye to her agent boyfriend Cpt John Guinness (Dario Michaelis).
In Holland the Dutch resistance leader, The Gorilla (Folco Lulli), leads an attempt to free the British agents from the abbey where they are imprisoned.
Der Spiegel wrote: “The busy Curd Jürgens in his best role for a long time as a humane and efficient head of “defense” in occupied Holland: The plot … goes back to a factual report, and the military events on the underground front may well correspond to reality.