Basque Country, Spain, late nineties. A young policewoman manages to infiltrate the ruthless terrorist gang ETA. The plot is based on true story on an undercover agent who infiltrated ETA under the name 'Aranzazu Berradre Marín' and managed to dismantle the 'Donosti' cell. Undercover (Spanish: La infiltrada) is a 2024 Spanish thriller film directed by Arantxa Echevarría starring Carolina Yuste and Luis Tosar. After spending several years infiltrating the circles of the Abertzale left as another young sympathizer of the terrorist group ETA, a police officer gets what she was looking for: ETA contacts her.