Zhang Lin transmigrates into Er Ya, her three-year-old adopted older sister who died young. After waking up, she uses her keen investigative skills to deduce that Er Ya's fall from the cliff was no accident: her paternal cousin-aunt, Zhang Yuzhen, deliberately pushed her down the mountain. When Zhang Lin awakens, her grandfather Zhang Yaowen, grandmother Chen Yuwei, and father Zhang Guosheng unexpectedly discover that they can hear her inner thoughts. Through her thoughts, they see Zhang Yuzhen's true colors: seemingly obedient and sweet on the outside, but vicious and malicious underneath.