From 1931-33 McWilliam lived and worked in Paris. On his return to London he worked in an independent manner but was in close contact with the British artists Henry Moore, Paul Nash and Roland Penrose. The International Surrealist Exhibition of 1936 made a significant impact on him and, during 1939-40, he made a striking series of carvings in wood and stone which he entitled 'The Complete Fragment'. These carvings were mostly part or parts of the human head, greatly enlarged and complete in themselves. McWilliam was interested in the interplay between solid volume and surrounding space in these works, and also how the viewer completes the 'missing' parts of the sculpture in the mind's eye.