Lee Kang soo, a street smart drug informant (known as a “yadang”) who works with an ambitious prosecutor named Goo Gwan hee. Kang soo, who was unjustly jailed for a drug related crime, is recruited by Goo to use his sharp memory and connections to gather intelligence on drug rings. Their partnership is a success, and Kang soo’s intel helps Goo rapidly rise through the prosecutorial ranks.
