Question Of Research - S1.E1

The episode opens with Amy complaining to Rupert that she has too much to do [looking after their flat and typing up Rupert's notes on top of her job as an artist] and she's going on strike. Later, while Amy is talking to Rupert's literary agent, a fake telephone engineer calls and plants bugs in their flat. The next day, a girl calls at the flat to return Rupert's wallet after his pocket has been picked by her colleague, and they offer her a live-in au-pair job. She moves in and is caught by Amy late at night looking through Rupert's desk - for one of his novels to read, she claims. The next day, Amy discovers one of the bugs and the couple speculate that they are the victims of mistaken identity? After all, there is a strange man living in the flat below who looks, for all the world, like a white slave trader?