Lloyd Nolan wears a Longines 13ZN

Island in the Sky (1953) was made by people who had done the flying themselves. William Wellman, the director, flew with the Lafayette Flying Corps in the First World War, and Ernest K. Gann wrote the screenplay from his own 1944 novel, which drew on a real Arctic rescue mission he had flown for the Air Transport Command. In the film, John Wayne's Captain Dooley puts his iced-up C-47 down on a frozen lake near the Quebec-Labrador border, and Lloyd Nolan's Captain Stutz is one of the fellow pilots who fly the search. The snow scenes were shot at Donner Lake in the Sierra Nevada, with surplus DC-3s handling the aerial work.

Stutz's watch gets its own insert shot, and the frame leaves little to argue about: a light dial with Longines printed plainly on it, Arabic numerals, two registers, a long center chronograph hand, a dark strap. It is a bicompax Longines chronograph powered by the caliber 13ZN, the movement Longines filed for patent in June 1935 and registered the following year. A few earlier Longines movements had carried a flyback, but the 13ZN was the caliber the patent was filed on and the one that used it widely: press once and the chronograph resets and restarts in a single motion. The caliber turned up again and again in big aviator's watches.

Longines built the 13ZN from 1936 to 1951, and it still ranks among the most prized Swiss chronograph calibers of its era. Production ended barely two years before the film reached theaters.