Consumed by questions of her grandfather's fate and the intoxicating world of Baumgaertner, Amy exists increasingly in a world of her own. The relationship between Deborah and Maurice is further deteriorating and Shun is caught between the warring couple. Plumber Donald is delighted to be asked round to Matilda's, where a blocked sink calls for the deployment of his special Machine. Maurice goes on a bender with Amy's friends, with Donald forced to play chaperone. Deborah focuses her attention on a reading of her self-help book, in which Amy finds a clue that feels like it could just unravel the entire mystery of her grandfather Felix...