The show is a spin-off of the 2005 television series Una famiglia in giallo, in which the actor Guido Caprino, who plays Luca Manara, appeared in a secondary role in the fifth episode titled "Biscotti al Veleno".
For the new series in which he plays the protagonist, Caprino claimed to have been inspired by Frank Zappa for the behavior and the facial expressions he used in portraying Manara, the actor being an admirer of the Italian-American composer and guitarist.
Manara, whose nonconformity shows in his yellow aviator sunglasses, his penchant for jeans and his motorcycle, (a Triumph Bonneville), was transferred from Milan due to his relationship with a superior's wife.
Unlike Manara, Rubino is from the area; she has just moved back and lives with her aunt, Caterina Bentivoglio (who was Scarpati's mother in the series Una famiglia in giallo) and her German Shepherd Brigadiere, who often discover important clues.
Because of this, Lara moves to Milan to attend a course for furthering her career and is temporarily replaced in the police station by Marta (Anna Safroncik), a colleague with a dark past who falls in love with Manara.
Recurring characters include: Lara's aunt, Caterina Bentivoglio and Brigadiere; the married police couple Serena Sardi and Augusto Toscani, who in the first series fall in love and get married, while in the second will have a daughter named Alice; the officers Pio Buttafuoco and Mario Barbagallo; the coroner Ginevra Rosmini, a seductive femme fatale; the superintendent Casadio, who does not appreciate Manara's methods but is forced to recognize his talents; and Ada, the owner of the agriturismo (farmhouse accommodation) where Manara lives.