A war correspondent in Egypt thinks a screen star on tour is a spy.

After being dragged from his eighth viewing of movie star Marcia Warren's last American picture, Homer Smith, star reporter for the Cavity Rock Times Leader , hears the news that his Northern California paper has been selected as the best small town newspaper in America. As a reward for the paper, Homer is sent to North Africa to write a series of syndicated articles entitled "The Small Town Looks at the War." When his ship is torpedoed in the Mediterranean, Homer finds himself adrift on a raft and pulls on board fellow passenger Philo Cobson. After they get ashore, Cobson, who is actually a Nazi spy, gives Homer his pipe and tells him that he is a member of British Intelligence. He then asks Homer to go to the Viceroy hotel in Cairo, find a Mrs. Morrison and give her a coded message. In Cairo, Homer locates the suspicious Mrs. Morrison, and tells her that he is working on a story to uncover the female leader of a spy ring known as "The Big Six." She then indicates to him that Marcia, who is performing at the hotel, is the leader. Although Homer is at first skeptical, after seeing Marcia convey an apparently coded message to her maid, Cleona Jones, using hand signals, he assumes that Mrs. Morrison's story is true. The next day, Homer applies for a job as her butler, using the name "Juniper Jones." Marcia knows that he is lying, but thinks that he is simply a down-on-his luck American and hires him, then immediately starts to argue over whether San Francisco or Beverly Hills is the best city in California. The next day, Homer secretly follows Marcia into an antique shop, and when she screams after seeing a mouse, rendering a perfect high C, a secret panel opens, observed only by Homer. Later, Mrs. Morrison, who herself is a Nazi spy, goes behind the panel and confers with her cohorts about a new radio-operated plane that is to crash into a transport carrying British troops through the Suez Canal. As the days pass, Homer and Marcia each becomes suspicious that the other is a spy, even though they are falling in love. One afternoon, he misunderstands a phone call Marcia makes to her dressmaker, Mme. Laruga, and determines to get her out of the house that night so he can search for the "prints" that were to be delivered. Before Marcia leaves, though, Colonel Woodhue of British Intelligence, who has come to believe that Homer is actually Cobson, arrives at her suite and asks her to search Homer's quarters. Although she has suspected that "Juniper" was a phony name, Marcia has difficulty believing that he is really Cobson. After Woodhue leaves, Marcia insists on going out with both Cleo and Homer. At a movie theater, each sneaks out on the other and heads back for the hotel. While Cleo and Marcia search Homer's room and discover his real identity card, which Marcia thinks is a fake, Homer searches Marcia's room, but finds only fan letters. When they both wind up in the darkened living room, Marcia draws a gun on Homer, and after each accuses the other of being a spy, Marcia quizzes Homer on his knowledge of California. After she concludes that he is not a spy after all, he discovers that the "prints" were just material for dresses. The next night, at a concert in the desert, Marcia sings, while Homer follows the antique store owner. When Marcia goes to a pre-arranged trysting place, but discovers only Homer's pipe, she goes home furious. Meanwhile, Homer overhears the antique shop owner talking with the spies, who are going to "the pyramid." As they drive off, Homer hangs on to the running board, then throws away bits of the program for Marcia's concert, alerting one of Woodhue's men. After Marcia accidentally breaks the pipe and finds Cobson's picture and identity card, she realizes that Homer has been telling the truth and is now in great danger. At the pyramid, the Nazis find Homer and are about to take him inside the edifice, which they open with a tuning fork, when he escapes to a plane, unaware that it is the radio plane. Soon Marcia and British Intelligence arrive at the now closed pyramid, not knowing where the Nazis are. When Cleo and her new boyfriend Hector show Marcia some hundred dollar bills, which Hector calls "C-notes," Marcia realizes that Homer was leaving a clue. After a few false notes, Marcia finally sings a perfect High C, the pyramid opens and the Nazis are captured. As the radio plane approaches the troop ship, British planes shoot it down and Homer safely parachutes to safety. Some time later, Homer and Marcia receive a telegram from his boss, who says that he has become the most famous newsman in America, and suggests that he co-star with his wife in a picture. Homer is unsure, until Marcia shows him how they will act, kissing in a closeup.