Une Femme disparaît

While vacationing in Europe, Iris Henderson meets kindly old Miss Froy (Dame May Whitty) on a train after passengers from Mandrika are delayed by an avalanche and crowded into an inn. After departure, Miss Froy vanishes during Iris's nap, yet fellow travelers deny any memory of her and a psychiatrist claims she never existed. Iris tracks her missing elderly friend, triggering an international incident amid spies, intrigues, love, and death over whether the defenseless old lady was truly innocent.