Lady Eileen "Bundle" Brent, is a fictional character of two of the Agatha Christie novels, The Secret of Chimneys (1925) and The Seven Dials Mystery (1929), described as a spirited "it girl".
Bundle was the eldest daughter of Clement Edward Alistair Brent, 9th Marquess of Caterham (simply called "Lord Caterham"). She had two sisters, Daisy and Dulcie. She described her late mother as having “got tired of having nothing but girls and died". Her mother "thought someone else could take on the job of providing an heir”. Bundle’s uncle, the 8th Marquess, was Foreign Secretary in the British Government (a circumstance possibly suggested by Marquess Curzon of Kedleston's having held that post from 1919–24).
The Brents' seat was Chimneys, a country house based on Abney Hall, Cheshire. The family’s residual links with the Foreign Office, including the presumption, resented by the 9th Marquess, that the house would continue to be available for purposes of state, as it had been when his late brother was in Government, were an important ingredient of the two Chimneys novels.
Bundle’s age is not explicitly given in either novel, but in The Secret of Chimneys, Bundle describes an incident that took place seven years before and says: "One of the footmen told me when I was twelve years old", which makes her 19 years old. That would be consistent with ages given or hazarded for characters whom readers would assume were, broadly speaking, her contemporaries. As a child she was "long-legged" and "impish", growing into a “tall, dark” adult with an “attractive boyish face”. She was resourceful, headstrong, vivacious and charming, with sharp, penetrative grey eyes that could be disconcerting to others.
Bundle was very much a young woman of her times, with many of the characteristics of a "flapper". Drawing on terminology made popular by the It (1927 film), Bill Eversleigh, one of the characters of The Seven Dials Mystery who had a crush on her, remarked to a colleague, "Don't you know Bundle? Where have you been vegetating? She's simply it". When Bundle's father, with whom she clearly had a strong bond, observed that "you modern young people seem to have such unpleasant ideas about love-making", she attributed this to her having read The Sheik ("Desert love. Throw her about, etc."), the novel by Edith Maude Hull (1919) on which Rudolph Valentino's celebrated film of 1921 was based.