Fraulein Doktor

Two German spies and a woman physician (Suzy Kendall) are taken by submarine to Scotland where they enter the country at nightfall. Their mission is to assassinate the British Field Marshall Lord Kitchener. The woman's male companions are captured, but she escapes with the knowledge of what boat the Marshall is on. Boarding the submarine, the Germans make plans to bomb the boat with a series of strategically placed land mines. (allrovi.com)