A surrealist artist, born in Buenos Aires, Agar returned with her family to England to attend school at Canford Cliffs, Dorset and Heathfield, Ascot (taught art by Lucy Elizabeth KEMP-WELCH), Tudor Hall, Chislehurst and the Mlles Ozanne's Finishing School, London. She also attended weekly classes at Byam Shaw School of Art and visited the studio of Charles SIMS. She spent a summer at Cap d'Antibes, where she was taught watercolour by William THORNLEY. Both of these artists had worked in West Cornwall previously. From 1921-4 she attended the Slade part-time, where she was taught by Professor Henry TONKS, but in 1925 she destroyed most of her work.
In July of 1937, Agar and her partner Joseph BARD, whom she married in 1940, stayed at Lambe Creek, Cornwall with fellow artists Roland PENROSE, Lee MILLER, Paul ELUARD and Nusch ELUARD [See Penrose]. In 1945, at the end of the WWII, she again visited Cornwall. And in 1960 she made visits to Venice and Cornwall. Shortly before her death, she was elected RA.