Count Five and Die

Count Five and Die is a 1957 British war drama produced by Zonic Productions and released in the USA by the Twentieth CenturyFox Film Corporation. It was directed by Victor Vicas, produced by Ernest Gartside with the screenplay by Jack Seddon and David Pursall. It stars Jeffrey Hunter, Nigel Patrick and Annemarie Dringer.

One night, while on a date with Rolande Hertog, the units radio operator, Ranson becomes concerned and returns to the offices. He is shot at and wounds an intruder. He leaves the unconscious man with Hertog to search further, but the mans accomplice gets away. Hertog kills the captive, claiming he tried to grab her gun. A romance quickly develops between Ranson and Hertog the same night. When Ranson gets back to the office, Howard criticises his actions MI5 had tipped him off that the Germans were planning to search his offices, so he made it easy for them to get the planted misinformation, until Ranson intervened. Further, he suspects that Hertog is a German agent Jan Guldt, their liaison with the Dutch underground, had been sent back to Holland, only to be captured immediately. Ranson does not believe it.Howard sends Piet van Wijt to Holland, supposedly to evaluate the effects of a bombing raid, but actually to test Hertog. They do not hear from van Wijt again. Meanwhile, Howard receives news that the Germans are redeploying troops into the country. ........

Source: Wikipedia