Catch The Ghost

The One That Got Away (1x12)

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One of the Grasshoppers gets away from the police. The other two Grasshoppers confess that they only know him as Han Tae Woong, although that name turns out to be a fake identity. The investigation reaches a dead end and Ji Seok is about to be reassigned to a remote island. Ryung comes up with a plan to save Ji Seok and to catch the Subway Ghost.