CEO Shen Zhou spends 20 million yuan to buy Xianxian, a mermaid, intending to use her scales and mermaid pearl to cure his fiancée Xia Enmian's migraines. However, Xianxian is obsessed with short dramas and imagines that Shen Zhou is deeply in love with her, becoming determined to replace Xia Enmian. She secretly drinks a potion that transforms her tail into legs, forcibly leaving the water, and even causes a false pregnancy scare, when in reality she is suffering from severe constipation after overeating. Along the way, she bites Xia Enmian and imprisons both her and the mermaid's caretaker. When Shen Zhou returns home, he is busy plotting to make a fortune by breeding mermaids, leading to one ridiculous mishap after another. When the truth finally comes out, Shen Zhou abandons his plans for profit, honestly expresses his feelings, and sends Xianxian back to the sea.