'Burning Bright' follows the Kellaway family as they leave behind tragedy in rural Dorset and come to late 18th-century London. As they move in next door to the radical painter/poet William Blake, and take up work for a near-by circus impresario, the youngest family member gets to know a girl his age. Embodying opposite characteristics - Maggie Butterfield is a dark-haired, streetwise extrovert, Jem Kellaway a quiet blond introvert - the children form a strong bond while getting to know their unusual neighbor and his wife.