Black Crown (1951)

A young engineer, Andrés, welcomes a young woman, María, who suffers from amnesia. Little by little, she discovers her past: she is the widow Russel and, in the hotel she comes to fetch her pieces of luggage, she meets her former lover, Mauricio. The latter confines her illegally for he is convinced that María's amnesia is all an act: he believes she does not want to tell him where the diamonds they stole from her late husband are hidden. As her past continues to resurface, she realizes she murdered Russel and that the precious stones were concealed in his coffin.