Overall the acting and story line was very well done. The story concerns a wife who was supposedly murdered by her husband, and buried alive, but lived and was found by a noble woman, who was sent to a religious institute, and her maid. The noble had been beaten and was treated badly and succumbed to her injuries. The wife assumed her other woman's identity and along with the maid vowed to avenge herself as well as the woman who's identity she assumed.
It was confusing in that the two didn't look anything alike, but since the noble was sent away when she was 10, they dismissed it as she changed while away. When the husband and family met the returned 'noble', they all almost fainted as she was a twin of the wife he supposedly murdered.
Of course, the wife/noble avenged everything, but now the confusion. The noble and her sister were both in love with the same guy, even tho one was 10 when sent away the other was when her sister was sent away. We're suppose to believe that everyone was still having the same feelings? The fake was saved by an investigator, Duke, and he was the Emperor's right hand man, even thou the two met 8 years ago,, when bother were about 8 or 9 years old. Every one are adults but the time lines don't match.
Lastly, at the end, the Emperor sends Duke to the north flank to save that border, but it looks as if he failed, but the closing credits we see a horseman (legs only no face) riding towards his wife (the fake one), but not sure if he was still alive or it was his wife's dream/vision?

If you can get by the timeline of the different characters, it's well worth watching as there are some awesome plot twits that you don't see coming.