Born in Whitchurch, Oxfordshire, Law was the son of an architect but his parents separated when he was quite young and he lived for a while, probably in the 1920s, with his mother and sister in Quimper in Brittany. His mother May LAW (Maisie), herself a keen amateur artist, encouraged his interest in art.

He was educated at St Petroc's School, Rock in North Cornwall, which was owned by a Miss Vivian who had a house in Lamorna. His family probably holidayed with her in Lamorna in these early years. Later he trained as an electrical engineer at Faraday House, and worked in the Home Counties during WWII.

After the war, he moved down to Lamorna with his second wife, Ann, as his sister was now the landlady of The Wink public house in the village. He took up painting full time, supplementing his income with a variety of odd jobs including fishing, copperwork, carving wood and making furniture, whilst his wife used a loom to weave textiles.  He was greatly influenced by the leaders of the Lamorna artistic community, but did not take lessons with either Lamorna BIRCH or Stanley GARDINER, preferring to approach the artistic challenges of the Valley on his own terms.