Time Between Dog and Wolf

After his mother was ruthlessly murdered in front of his eyes by the Thai criminal syndicate known as Cheongbang, Lee Soo Hyun is adopted into NIS agent Kang Jung Ho's family. Together with Jung Ho's son, Kang Min Gi, Soo Hyun becomes a NIS agent. When Soo Hyun meets Suh Ji Woo they were about twelve years old and was able to cross paths again 13 years after.