ObscureHollywood.net’s review published on Letterboxd :
Archduke Rudolph (Charles Boyer), son of Emperor Franz Joseph, is deeply unhappy. He has a loveless marriage of state, no duties or influence in the affairs of the empire, and a wasted, boring life. He spends his time carousing with the members of his regiment and making love to one woman after another. Rudolph’s life changes after he meets beautiful, seventeen year old Countess Maria Vetsera (Danielle Darrieux). He falls in love with the innocent, warm-hearted girl. Rudolph’s petition to divorce his wife in order to marry Maria is denied by his father. The Emperor threatens to send Maria to a convent if Rudolph does not separate from her. In despair, Rudolph and Maria agree to protect their love and put an end to their unhappiness. They travel to Mayerling, a hunting lodge, where Rudolph carries out their suicide pact, killing Maria and himself.
Boyer and Darrieux are appealing and sympathetic as the doomed lovers.