The narrative begins with Dong-cheol in a precarious financial situation after investing in a Russian king crab shipment. Following a minor traffic incident with Gi-tae, Gi-tae's criminal syndicate targets and abducts Ji-soo. Gi-tae executes his signature modus operandi by leaving a bag of cash for Dong-cheol, believing that desperate husbands will gladly abandon their wives for money.
Dong-cheol rejects the payout and joins forces with Choon-sik and Inspector Gom to track down the syndicate. They interrogate low-level associates and infiltrate an underground casino used to traffic victims and smuggle pharmaceuticals. Meanwhile, Ji-soo acts proactively by coordinating an escape attempt alongside fellow captive So-yeon before being recaptured.
In the high-octane climax, Dong-cheol attacks Gi-tae's main compound, demolishing syndicate enforcers with brute force. Following a vehicle pursuit, Gi-tae crashes his car and receives a devastating beating from Dong-cheol. Preserving his moral reform, Dong-cheol spares Gi-tae's life and leaves him for the arriving police while rescuing Ji-soo and the other captives. In the epilogue, Dong-cheol's king crab investment unexpectedly pays off, allowing Dong-cheol and Ji-soo to run a prosperous seafood restaurant surrounded by friends.