Her first two novels were co-written with a college friend, Gertrude Winifred Taylor: Chantemerle: A Romance of the Vendean War (1911) and The Vision Splendid (1913) (about the Tractarian Movement).

[5] The Yellow Poppy (1920), about the adventures of an aristocratic couple during the French Revolution, was later adapted by Broster and W. Edward Stirling for the London stage in 1922.

She wrote several other historical novels, much reprinted in their day, although this Jacobite trilogy, inspired by a five-week visit to friends in Scotland and featuring the dashing Ewen Cameron as hero, remains the best known.

Literary historian Jack Adrian describes Couching at the Door as "a pure masterwork, one of the most satisfying weird collections of the century".

[9] The poet Patricia Beer was an admirer of Broster's novels, stating she had been fascinated by The Flight of the Heron when she read it aged thirteen.

The Flight of the Heron was serialized on TV twice: by Scottish Television in eight episodes in 1968, and by the BBC in 1976, which starred David Rintoul as Ewen Cameron and Tom Chadbon as Keith Windham.