Infamy, power and privilege are the themes of Katherine Moar’s short, snappy and hugely enjoyable second play. It’s inspired by Patty Hearst, the media heiress kidnapped by purported US guerilla group the Symbionese Liberation Army in 1974 and later convicted of robbing banks with them, though she was coerced and raped. Moar’s debut, Farm Hall, was about the Allies eavesdropping on captured German atomic scientists in a country house, and it transferred from Jermyn St to the Haymarket. Diffuse ideas spark interestingly in this writer’s mind.