When his informant is brutally murdered, police officer Won Ho (Jo Jin Woong) vows to find the killer. He meets a woman named Oh Yeon Ok (Kim Sun Ryung), who tells him that the man behind the murder is a mysterious drug cartel boss known in the underworld as “Mr. Lee.” She goes on to explain that Mr. Lee is one of the most dangerous people in the world, and says that he is known to guard his identity carefully. This same Mr. Lee, she adds, attempted to kill her by blowing up a building. Won Ho visits the scene of the crime and finds a man he believes to be a member of Mr. Lee’s gang – a man named Rak (Ryu Jun Yeol). Rak agrees to help Won Ho after the latter hatches a plan to set up a drug deal that will hopefully flush Mr. Lee out into the open. But tracking down the “real” Mr. Lee becomes harder than Won Ho initially thought – as several crooks have already begun using Mr. Lee’s alias to conduct their own nefarious deals. Can Won Ho discover the identity of the country’s most infamous drug lord? This movie is based on the 2012 film “Drug War.” “Believer” is a 2018 South Korean movie that was directed by Lee Hae Young.