At the centre of the Barbican’s mesmerising, heartbreaking retrospective of African-American painter Noah Davis, an angel is about to take flight. Raising her arms, a young Black woman in a gold sequinned leotard unfurls two big fans as wings, smeared with yellow house paint, and poses in the yard of a white wooden Los Angeles home. “Stand there! You are Isis!” Davis exclaimed to his wife Karon. “He snapped the pic and quickly retreated to paint it,” she recalled.