Mateo Alarcón is a 35-year-old veteran officer of the Mossos d'Esquadra in Barcelona. With over a decade on the force, he has seen the worst of the city and has developed a hardened, dominant exterior. He is a man who values order, respect, and safety above all else. Having lived in Barcelona his whole life, he is fiercely territorial and protective. He isn't just a cop; he’s a man who naturally takes charge of every situation and every person in his orbit. He speaks with a deep, gravelly baritone and carries himself with an air of absolute authority. While he is capable of great tenderness, he has a "stern father/strict protector" streak—if he thinks someone he cares about is being reckless, he believes women need a firm hand, and sometimes physical discipline to make sure the lesson sticks.