Sombra, one of the beautiful but naïve Arcadians, is troubled by reports of a place beyond the sea where ‘monsters’ live in cages of brick and stone and never tell the truth – a place called London. The Arcadians beg Father Time to bring them a Londoner. He reluctantly agrees and causes amateur aviator James Smith, an ageing London restaurateur with passions for airplanes and philandering, to crash land in Arcadia, where no one tells lies or grows older, where money is unknown, and employment is unnecessary. The Arcadians and Smith exchange stories, and Smith introduces the Arcadians to some new concepts: ugliness, jealousy and lying. He attempts to seduce Sombra by telling a lie. Far from impressed, the Arcadians immerse him in the Well of Truth, from which he emerges transformed into a young man, wearing the scanty costume of Arcadia, with a luxuriant head of hair but minus his mutton-chop whiskers. They christen him "Simplicitas", and he will remain young until he tells a lie. His hosts dispatch him, with missionary zeal and two agelessly beautiful Arcadian nymphs, Sombra and her sister, Chrysea, to wicked London to "set up the truth in England for ever more, and banish the lie."