The Viper Brothers: The Blackmailers (1973)

When Koryu's childhood friend Shurei is abducted by gangsters, the desperate young woman recruits a female martial artist and a tough-as-nails stranger to join her for a dangerous rescue mission.

Billy Wong is a New York City cop whose partner is gunned down during a robbery. Billy and his new partner, Danny Garoni, are working security at a fashion show when a wealthy man's daughter, Laura Shapiro, is kidnapped. The Federal authorities suspect that Laura's father is involved with Mr. Ko, a Hong Kong drug kingpin, so the NYC police commissioner sends the two cops to Hong Kong to investigate.

Former yakuza underling Kazuma Kiryū has recently been released from prison after a lengthy incarceration and is trying to piece his life together and distance himself from his yakuza past. Unfortunately, Kiryū's problems slowly escalate as he is pursued by a former associate, the baseball-bat-wielding psycho Gorō Majima, who has a grudge to settle with Kiryū.

Ocho is accidentally captured by a drug trafficking cartel who use Chinese women to smuggle drugs into Japan by hiding it in their vaginas. She is tortured, and manages to escape, fighting both the male yakuzas and a gang of female thieves.

Li Mansei is a martial-arts champion turned undercover agent. When he is captured by a drug lord, his sister Li Koryu turns to his former martial-arts school, including the powerful Sonny Kawasaka, for help in the inevitable battle royale.

In an alternate version of 1949 Japan in which World War II never happened, the Japanese capital of Teito is home to both an ultra rich upper class and the dirt poor masses. The city is thrown into a state of panic when a phantom thief called “The Kaijin (Fiend) with 20 Faces” (K-20 for short) begins to use his mysterious abilities to steal from the rich and give to the poor. One day a circus acrobat named Heikichi Endo (Takeshi Kaneshiro) is framed for K-20’s crimes and becomes determined to clear his name. He teams up with K-20’s next target, a wealthy duchess named Yoko Hashiba (Takako Matsu) and her detective fiancé (Toru Nakamura), to take K-20 down once and for all.

When Nick Davis leaves prison after one year in solitairy, he is hired to operate a forklift in a warehouse in the harbor owned by the Japanese Yakuza patriarch Isshin Tendo. The place is assaulted by the Italian Mafia lead by Dino Campanela and Nick rescues and saves the life of Shuji Sawamoto, who is the representative of Yakuza interests in America. Shuji hires Nick to work for Yakuza and becomes his godfather in the family after his oath to join Yakuza. However, Nick is a lonely FBI undercover agent assigned to penetrate the criminal organization. When the FBI discovers that Campanela is organizing a massive attack to destroy the Yakuza, Nick's boss Littman calls off the operation to leave the dirty work to the Italian Mafia. But the connection of Nick with Shuji and his goddaughter Yuko forces him to help his Japanese family.

When a young Yakuza torments the customers in a rival crime family's nightclub, it is not long before his dead body is found. Soon, inter-family retaliation follows, resulting in the death for a prominent crime boss. Devastated by this turn of events, the temperamental Kenzaki vows to avenge his boss's death and, as bloody violence ensues, the body count reaches excessive proportions.

Brazilian-Japanese gangster Mario rescues his Chinese girlfriend Kei as she's about to be deported from Japan. Desperate to escape, he hides in Tokyo's booming Japanese-Portuguese community and seeks passage from the country from a Russian mobster. To meet his price, they hold up a bigtime drug deal between the Chinese Mafia and the local Yakuza.

Ryūichi and his small gang of Triad vie for control of the Japanese underworld in a crime-ridden Shinjuku quarter while Detective Jojima tries to bring it down.