Freddie Clegg, a neurotic London bank clerk and amateur lepidopterist, wins a football pool. Now financially secure, he resigns from the bank and purchases an estate in Sussex, which he furnishes in anticipation of a visitor. He then abducts Miranda Grey, an art student. Certain that in time she will come to love him, he sequesters her in a basement apartment in his manor. At first bewildered, Miranda unsuccessfully attempts to cajole, then seduce, her keeper. Desperate, she smites him with a spade. Stunned, Freddie nevertheless again imprisons her. He goes for medical attention, returning 3 days later to find his prisoner expiring, the basement furnace having given out in his absence. After burying Miranda, Freddie searches for a substitute. He decides that a nurse will be a most suitable specimen for his collection.