Edith Caroline Rivett (6 May 1894 – 2 July 1958) was a British crime writer, who wrote under the pseudonyms E. C. R. Lorac, Carol Carnac and Mary Le Bourne during the golden age of detective fiction.

[1] When the family reached London, they were literally penniless but were received into the welcoming, if crowded, household of Beatrice Rivett's father, Edward Foot, and the widow found employment as an assistant rate collector.

John Curran, historian of the Crime Club, argues that she was especially well served by the designers of the cover artwork for her books, and this is no doubt one of the factors that has made her work especially collectable.

Like Rosanne Manaton, a character in her Checkmate to Murder, she was artistic and had an interest in ski-ing; the winter sport plays a central part in her Carol Carnac novel Crossed Skis, also published by the British Library.

A previously unpublished late work, Two-Way Murder, was added in 2021; the original manuscript was under a new pen name, 'Mary le Bourne', but has been published by the British Library as by E.C.R.

[6] The back cover of the re-issued, Fire in the Thatch: A Devon Mystery (originally published in 1946), declares that, "Her books have been almost entirely neglected since her death, but deserve rediscovery as fine examples of classic British crime fiction in its golden age.

Most of these books feature her main series character, Chief Inspector Robert Macdonald, a "London Scot" and an avowed bachelor with a love for walking in the English countryside.