Don't Mess with My Sister Ep. 4

She, a gentle and timid illegitimate daughter of a wealthy man, suffers abuse from her husband's family after marriage. When the wealthy man unexpectedly dies, she is the sole heir to his fortune. Her husband hires someone to kill her to seize the inheritance, but the hired woman looks exactly like her. After a struggle, they both pass out and their identities are mistaken. The straightforward and tough hired woman, at the request of others, helps her reclaim the fortune. They soon discover that they are actually twin sisters. Together, they set out to uncover the truth about their parents' deaths and seek revenge on her husband's family.