In the grey city of Nordby, where they fear everything blue, lives the hotel receptionist Anne. She dreams of becoming one of The Grey, the city's protectors. One night Anne sees a blue cat by the hotel. She imminently calls The Grey to the scene, who unsuccessfully starts a mission to catch the cat. Meanwhile, a young and colourful couple, Al & Chris, arrive at the hotel. Their different way of looking at the world and dangers of the blue cat challenges Anne's faith in The Grey. When the cat suddenly gets caught in a trap near the hotel, Anne has to decide whether she wants to free it and leave the city, or turn it in to The Grey and keep following the city's strict code.