Alberto (Salva Reina) has dreamed since childhood of being the next Sherlock Holmes, but along the way he has remained a security guard at a shopping center. It has everything you need for it, except for the detective license you just suspended for the fifth time. After a series of personal misfortunes, he will have to move to live with his sister-in-law Marta (María Esteve) and his two nephews. But everything changes when he meets Max (Ramses), a new companion capable of successfully carrying out any mission that is proposed. All great if it were not for a small detail that makes it unique: it is an adorable Jack Russell dog with the ability to speak. Max and Alberto will not only have to face the most complex cases, but they will also have to figure out how to do it in such a way that neither his family nor the police will discover Max's secret abilities. The only ones who know them are their colleagues in the criminal organization for which they worked, and therefore they will try to eliminate him. But Max has other qualities besides being a talking dog. He is intelligent, deductive, professional and, above all, capable of upsetting Alberto in any situation. In spite of everything, Holmes already has found his Watson, and together they will create 'Hounds', the agency of detectives with which he will be able to fulfill the dream of his life.