Samurai Code — Don Easton

After a cheap handgun sets Jack on the trail of a heroin importer, he winds up in the lair of one of the largest Yakuza crime families, caught in a deadly clash of criminal cultures.

This intriguing, suspense-packed novel is the fourth in the Jack Taggart Mystery series, continuing the story of Loose Ends, Above Ground, and Angel in the Full Moon. This time, the implacable Mountie Jack Taggart goes undercover to follow the trail of a cheap “Saturday-night special” handgun found at the scene of a murder.

He traces the gun from the manufacturer to the person it was stolen from, and through several criminals, until the trail leads him to a suspected heroin importer. Posing as an Irish gangster to penetrate the criminal organization, Taggart discovers that the real crime boss is a mysterious figure out of Asia.
Alone and without backup in the lair of one of the largest Yakuza organized crime families in Japan, Taggart finds himself caught in a deadly clash of criminal cultures.