After many tests, she finally gained a foothold in the palace, but unexpectedly gave birth to a "mermaid baby" with a blue fish tail. In order to keep her children safe, she resolutely gave up her wealth, planned to escape from the palace, and lived in seclusion in a seaside town. However, the special physique makes the life of mother and son on thin ice. The neighbors' temptations and the sudden high fever make crises come one after another. Looking at the child's innocent face, the blurred memory of that night in the garden water resurfaced again - what kind of shocking secret does that emperor who reigns over the world hide? This is an escape about courage and love, just to protect the only treasure.