Zeppelin

In the early days of World War I, constant bombing raids by German dirigible aircraft known as "Zeppelins" become a central issue for the British Admiralty. Young British officer Geoffrey Richter-Douglas, a Scotsman with German heritage, reports on the Zeppelin attacks and learns from a secret demonstration that the hydrogen-filled airships are not susceptible to gun shots, but only to incendiary bullets. Aware that Geoffrey, whose German relatives are aristocrats, has been approached by German spies to work for them, British intelligence encourages Geoffrey to go to Germany as a double agent. Although uncertain, Geoffrey agrees and on the night of his departure is purposely wounded in the arm to impress the Germans of the genuineness of his escape. In Germany, Maj. Johann Hirsch and Maj. Alfred Tauntler from military intelligence welcome Geoffrey, who, they are delighted to learn, can easily identify isolated spots in the Scottish countryside. After his interrogation with Hirsch and Tauntler, Geoffrey runs into old family friend and Zeppelin designer, elderly Professor Christian Altschul. Revealing that he has recently remarried, Altschul invites Geoffrey to dinner the following evening to meet his wife Erika. The next night, Geoffrey arrives at the Altschuls' apartment early and is greeted by the young, attractive Erika, who startles Geoffrey by asking him if he is a spy. Erika explains that she is a former student of Christian's and has helped design the latest Zeppelin model, the Z36. When Christian telephones moments later to report a problem with the new ship, Erika tells Geoffrey their dinner must be postponed, then unsettles him by cautioning him to take no action that might harm her husband. The next afternoon, Geoffrey reaches his British contact, but when he reports that the test flight for Z36 has been delayed, the contact relates that information has long been known. That evening while returning to his apartment, Geoffrey is forced into a car by military police and taken to a large, darkened field where, to his great surprise, he finds the Z36. Hirsch and Tauntler are at the site and invite Geoffrey to make the airship's test flight with them, which they admit is top secret. Realizing reports of the ship's test being delayed have been a ruse, Geoffrey agrees to go aboard, struggling to squelch his long time aversion to heights. After the Z36 departs the airfield, Erika unnerves Geoffrey by observing that he is doing very well for a spy. Under the control of Christian and the ship's captain, Lt. Cmdr. Von Gorian, the Z36 breezes through speed and altitude tests the next day and the professor declares the Zeppelin ready for service. Hirsch then surprises Von Gorian by announcing that the Z36 will not return home but instead is to go into immediate military duty. Meanwhile, pleased over the ship's test results, Erika chats with Geoffrey and confesses that although Christian was deeply distressed to learn the Zeppelins were used for bombing missions, he is so enthralled with the technical design that he has continued working on them. Abruptly realizing the ship has changed course, Erika and Geoffrey confront Von Gorian, who admits the ship is now under Hirsch's command. Hirsch directs the great ship to a river, where naval personnel await on a pier to refuel the craft. When most of the crew exits the Z36 to assist, Geoffrey hastily sends a Morse code message to British intelligence reporting the ship's Norwegian position. When the radio operator returns and hears a confirmation, Geoffrey is forced to kill him. Later, when the ship ascends to freezing, high altitudes and the crew must scrape off forming ice, Geoffrey tosses the dead man overboard and reports that he fell out. Hirsch accepts Geoffrey's explanation, but Erika remains suspicious. Late in the afternoon, after the Z36 rendezvous with a ship to load numerous soldiers and tubes of mustard gas, Christian protests vigorously. Hirsch and Tauntler then reveal their mission: to break into the British Archives, housed in Scotland's Balcoven Castle, and steal historical documents, including the Magna Carta, to completely demoralize the British. Once aware of the Z36's destination, Geoffrey attempts to send another Morse message, but is followed by Erika. Although Hirsch questions them, Erika does not give Geoffrey away. That evening as the craft crosses into Scotland, Tauntler orders Geoffrey to get into a small basket with him, which will be lowered from the ship, enabling them to guide the pilot directly to the castle. To Geoffrey's delight, he discovers his vertigo has disappeared. As the Z36 descends under Geoffrey's guidance, a local farmer hears the engines just before they are cut and reports it to the local military base. After the ship lands, the German soldiers silently infiltrate the castle, taking the guards by surprise. Forced to participate in the raid by Tauntler, Geoffrey evades the soldiers in the dark to locate the communications room, where he pleads with a skeptical operator to contact London. Once the Germans begin firing on guards and setting off explosives to reach the archive safe, the operator reacts, but, certain Geoffrey is German, wounds him in the arm. Alarmed by the farmer's account and a fleeting report from Balcoven of the attack, the British Admiralty orders numerous air squadrons aloft and sends ground troops to the castle. As the troops break up the German attack, Geoffrey steals a flare gun and rushes back outside, hoping to destroy the Z36. Inside the castle, Hirsch detonates a bomb in front of the archive safe, but although the heavy door is partially damaged, the Germans are unable to remove any documents before Tauntler orders a withdrawal to save the Zeppelin. At the craft, Erika confronts Geoffrey and tells them that if he destroys the Zeppelin he will kill Christian, who is still onboard. Retreating soldiers help the wounded Geoffrey back on board and with only a few crew members, the ship takes off despite suffering numerous gunshots. As dawn breaks, Von Gorian suspects British planes will be after them and orders all surplus weight to be thrown overboard to help the ailing ship ascend. Erika tends to Geoffrey, but does not respond when he asks why she has not betrayed him. British squadrons close in on the Zeppelin and a gunfight ensues in which several airplanes are shot down and Von Gorian is killed. As the dead are thrown out to lighten the ship, the seriously wounded Tauntler throws himself out. After the battle, Erika and Geoffrey hunt for Christian and, finding his cabin empty, conclude he, too, threw himself overboard to save his ship. Spotting land that they recognize as neutral Holland, the wounded pilot makes a crash landing a few yards from shore and Erika, Geoffrey and the remaining crew members stumble to shore just as the craft explodes.