A South Korean agent hunts a drug ring in Russia and goes head-to-head with a North Korean operative — pulling both into peril and tangled secrets.

Seo Munju, a highly accomplished diplomat and former ambassador to the United States, and Sanho, an international special agent shrouded in a veil of secrets, race to uncover the truth…

Navigating both the criminal underworld and law enforcement agencies, professional snitches called “yadang” provide covert information about the drug world to prosecutors and police. When a drug bust at a…