The Truth Within Episode 14

A new body found in a dumpster links a current murder to a fourteen-year-old cold case involving a dead artist. The victim is identified as Hu Jie, the friend of the original cold case victim. Forensics reveal the killer uses a fountain pen and is left-handed. The investigation leads to an art agent named Ruan Ming Yu, who flees when Han Feng connects him to the original crime scene. (Source: C-Drama Tracker)