The Substitute Bride's Revenge

On the wedding night, Princess Consort of Ning Wren Ling died mysteriously. Her sister Wrenna Ling, expert in medicine and poison, impersonates her to investigate. The palace is full of treacherous people: Nina Su frames others, Willa Jiang schemes, Prince of Ning Ethan Xiao has a strange poison, Crown Prince Jasper Xiao assists. Wrenna Ling uses medicine to test everyone, uncovering intentions. Past affairs and unsolved poison cases are intertwined, a mastermind hides, truth indistinguishable.