Best known for her original and instantly recognisable paintings. Often comical, her works pictured people whom she encountered in everyday life, including people enjoying themselves in pubs, girls shopping or out on a hen night, drag queen shows or a family picnicking by the seaside or abroad. She had no formal training and did not take up painting until her thirties. She was a shy and private person, and in her art often depicted the flamboyant and extrovert characters she would like to be. Cook admired the work of the English visionary artist Stanley Spencer, his influence evident in her compositions and bold bulky figures. Another influence was Edward Burra, who painted sleazy cafes, nightclubs, gay bars, sailors and prostitutes, although, unlike Burra, she did not paint the sinister aspects of scenes. She had an almost photographic memory. Although widely popular and recognized as one of the most well-known contemporary British artists, Cook never enjoyed acceptance by the art establishment.