The film begins with Vega Aircraft Corporation employees pilot Bill Morley (Joseph Cotten), a former Flying Tigers awaiting commissioning with the United States Army Air Forces and his comedy relief sidekick Rosey (Gus Schilling) blood donation for the American Red Cross. During their mandatory rest period following the donation, the pair sight a bevy of photographers following singing socialite Penny Craig (Deanna Durbin) giving her donation. As all donors are given the temporary use of hospital white coats, wolf bachelor Bill sees his chance to get Penny's address and details by impersonating a doctor.