She Faded into Air is a 1941 mystery novel by the British writer Ethel Lina White, originally published by the Collins Crime Club].

[1] It received relatively mixed reviews, but White followed it up with her success Midnight House in 1942.

Shortly after entering Pomerania House, a converted London eighteenth century mansion now used for business, Evelyn Cross vanishes into thin air.

Due to her prompt assistance in the matter, out-of-work film extra Viola Green is hired as a companion for the daughter of an American millionaire.

Despite their extra vigilance, the millionaire's daughter is then kidnapped from Pomerania House in similar circumstances.