In Narcos, Mateo “Cockroach” Moreno is an exile from Chile.
Moreno is introduced as a Chilean drug chemist and exile who encounters Pablo Escobar before the Medellín Cartel becomes a major international trafficking organization. He proposes producing cocaine while Escobar uses his smuggling experience and contacts to distribute it, establishing the partnership that helps launch Escobar’s cocaine empire.
The character’s backstory is tied to the 1973 Chilean coup d’état. In the show’s opening episode, drug makers are targeted during the political upheaval; Moreno survives, leaves Chile, and eventually brings his expertise to Colombia. Narcos uses him to dramatize how criminal networks and technical knowledge crossed national borders in the early cocaine trade.
Viewers sometimes confuse Moreno with Colombian cartel figures because most of his story takes place in Colombia. His nickname, “Cockroach,” is also translated as “La Cucaracha.” The character is not from Argentina, Bolivia, or Peru: the series specifically identifies him as a Chilean exile.