When Commander Raphaëlle Coste visits the police records bureau in search of information for one of her enquiries, she has no idea that she is about to have a life-changing encounter. The brilliant but unsettling young Astrid is autistic and a living enclyclopedia of criminal investigations. She has Asperger's, which makes her very original and rather finicky in some situations. When she gives Raphaëlle a helping hand, the two realize that their perfectly complementary skills are the key to solving cases, despite or even because of their differences.