Operation Amsterdam

In May 1940 the British government decides to dispatch a small team to the Netherlands aboard HMS Walpole with the objective of securing stocks of industrial diamonds before the Germans can seize them. The operation relies on a clandestine collaboration between Dutch diamond experts and British intelligence. The ultimate goal is to safeguard the diamonds for Britain in case of occupation.

Jan Smit, Walter Keyser, and British Army Major Dillon are dropped by ship onto the Dutch coast as the invasion unfolds. They survive a German air raid and narrowly evade a suspicious Dutch policeman who could blow their cover. The team begins the dangerous relay toward Amsterdam.

In need of transport, the group hijacks a car driven by Anna, a woman struggling with guilt over her Jewish fiancé's parents' deaths. Anna reveals herself as a member of the Dutch security forces and agrees to help the mission. Her reluctant trust becomes essential to the plan.

The quartet travels to Amsterdam where they meet Jan's father, Johan, at his diamond business house. Johan agrees to persuade other dealers to bring their diamonds later that day for transport to Britain. The plan to assemble the diamonds moves from theory to a hands-on operation.

Most of the diamonds are stored in a bank vault that cannot be opened for 24 hours because of the Whit Monday holiday. To access the diamonds, they recruit Dillon's contacts and a Dutch resistance group to help break in. The date compresses the suspense, forcing rapid coordination.

Fifth-column elements within the Dutch army launch an attack outside the bank, disrupting the operation. Despite the danger, the resistance fighters and the team manage to breach the vault and recover the diamonds. Jan eliminates the movement's leader, a Dutch army lieutenant, in the firefight.

As the defense holds, the four agents and Anna slip away from the immediate danger and head for the coast. They dodge a German air attack on their route back, but their boatmaster is killed in the process. The escape proves costly but successful in broad terms.

With the diamonds secured and the path to Britain open, the group commandeers a tugboat to take them back to the waiting destroyer. The route remains perilous as they contend with renewed German threats and the loss of their boatmaster. The final leg of the mission includes a tense maritime dash.

In a poignant turn, Anna elects to remain in the Netherlands and work with the nascent resistance movement. Her decision demonstrates a personal commitment beyond the mission and signals a longer, unresolved engagement with the local resistance. The team must continue the war effort with new local support in mind.