She worked for the Voluntary Aid Detachment during the First World War and designed and created recruitment posters for both it and the Women's Royal Naval Service.
Examples of her oil paintings are held by three museums and a blue plaque has been installed at her Budleigh Salterton home since April 2015 to commemorate her life.
[4] She was the daughter of the Indian Staff Corps captain Charles John Dennys who was stationed in the country and his wife, the Scottish-born housewife Lucy Winewood (née Tulloch).
[6] During the First World War, she served in the Voluntary Aid Detachment (VAD) as a member of the Joint War Committee of the British Red Cross Society and the Order of St John at Budleigh Salterton Auxiliary Hospital in the local Budleigh Salterton hospital nursing wounded soldiers between December 1914 and December 1915.
Dennys was commissioned to create a series of pictures for three editions of the book Our Hospital ABC that was written by Hampden Gordon and MC Tindall published by John Lane for both the 1916 and 1917 Christmas periods.
[1][7] Dennys was in high demand in the state and her works were frequently exhibited at the New South Wales Society of Artists and the Salon of Fine Art, Sydney.
She continued to work as an artist, exhibiting pictures of her time in Australia at the Suffolk Street Galleries by the Ridley Art Club that October.
Dennys wrote the play Rain Before Seven about an young English wife's loneliness in Australia and provided Maurice Denham's London stage debut in 1936.
She continued to write a variety of plays catered mainly for amateurs and frequently supplied the cover illustrations to Samuel French and H. F. W. Deane between the late 1940s to the early 1960s.
[9] For that year, Dennys' paintings of Budleigh Salterton were put online by the BBC in partnership with the Public Catalogue Foundation since several works held by Fairlynch Museum were included in the national collection.
[11] The British Red Cross and Museum holds a hand written note accompanied by drawings from the First World War by Dennys in its collection.