In the middle of the night, Annette Martial, a 22-year-old nanny, is found dead at the home of her employers, Edouard and Margaux Laroque. Alice and Marquand interrogate them and also try to find out more about the victim. But many grey areas remain around it. Soon after, Marquand discovers that the Laroques were spying on Annette via a camera hidden in a teddy bear.
