Chen Haisheng, a demobilized soldier returning to his hometown, bumps into the Lin sisters being forced to pay debts by a bully just as he reaches the village entrance. His parents have gone missing at sea, leaving behind only a dilapidated house and a growing IOU. Haisheng steps forward, makes a promise with a deadline, and takes the sisters to comb the tidal flats for mud crabs, harvest sea cucumbers from reefs, and gather rare seafood from sheer cliffs. These perilous environments trade for survival and also lead the three of them to discover clues that their parents might still be alive. To sail toward the deserted reefs thirty nautical miles away, Haisheng saves up money to install a diesel engine. Amid wind and waves, can they bring back their missing loved ones and safeguard the hard-earned new life?