Wildfire at Midnight

Wildfire at Midnight is a novel by Mary Stewart which was first published in 1956. Stewart herself described the book as "an attempt at something different, the classic closed-room detective story with restricted action, a biggish cast, and a closely circular plot".

Fashion model Gianetta Brooke leaves her usual glamorous surroundings to go on holiday to the Scottish island of Skye, only to find that her ex-husband, writer Nicholas Drury, is staying at the same hotel in Camasunary. Set against the backdrop of recent events at the time of publication—the coronation of Queen Elizabeth II and the Hillary expedition that was the first to reach the summit of Mount Everest—this romantic suspense novel now has a "bygone era" sense of time and place.

After two murders take place locally, suspicion falls on the hotel guests, who include an aging "femme-fatale" movie star, a possessive mountaineer and her ingenue apprentice, and a writer of travel guides. Gianetta, having become friendly with fellow traveller Roderick Grant, eventually discovers that Grant is a deranged killer hiding behind a mask of sanity. She is saved from becoming his next victim and reunited with Nicholas.

The mystery component lightly blends mountaineering, druid mythology, and pagan ritual, as distorted in the mind and actions of an insane killer who resents human arrogance in conquering nature. Add in a dash of Separate Tables interaction among the guests at the hotel and mix in a killer among them for traditionally entertaining suspense intrigue.

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Wikipedia