Watch Third Generation Acting Boss 4 (2015) Official Trailer

After the anti-yakuza laws drove the yakuza out, state power took their place, draining every last drop of profit. The Kanagawa Prefectural Police secretly control the drug market. Sakaki (Sho Aikawa), the third leader of the Kanto Kurogane Union, which promotes the decline of the nation and the eradication of drugs, sends his right-hand man Hidari (Hideo Nakano) to infiltrate the narcotics division under the department head, Rizaki (Hitoshi Ozawa), who oversees the drug market. A bloody purge by Sakaki begins against the police, who enrich themselves through yakuza and mafia-like tyranny!