Weed smoking, foulmouthed Rocco Schiavone is an offbeat Deputy Commissioner of the State Police. For disciplinary reasons he is transferred to the Alpine town of Aosta, far from his beloved Rome. The sophisticated but cranky Roman despises the mountains, the cold, and the provincial locals as much as he disdains his superiors and their petty rules. But he loves solving crimes.

Blanca Ferrando is a young woman who became blind at the age of twelve, due to a dramatic fire in which her older sister Beatrice died and which was caused by her violent boyfriend, Sebastian. This tragedy made her develop a very strong sense of justice to the point of pushing her to join the police. Blanca is helped by her most trusted friends: her guide dog Linneo, a female bulldog who protects and comforts her in the most difficult moments, and her beautician friend, Stella. After overcoming her work challenges, she finds herself facing sentimental ones: torn between two men, Inspector Michele Liguori, a man of many secrets, and Nanni, a young cook.

During the traditional carnival celebrations, the dead body of a young girl is found near the small town of Bellinzona, in Southern Switzerland. The officers engaged in the case find themselves investigating crimes rooted in a past full of shadows.