Brussels. Leo, a Spanish metro driver, while conducting his train and arriving at a station, sees a young man in distress on the edge of the platform. He recognizes his son Hugo right before he falls onto the rails and then dies at the hospital. Leo, who had not seen his son for years, will discover that he was involved in a bloody heist. While on the trail of his son’s murderers, Leo will be closely watched by the police, also investigating. They will soon discover that Leo’s skills in tracking and apprehending violent criminals are not those of a mere metro driver.