Queen Woo

Woo Hui is the queen of Goguryeo. A crisis ensues when her husband, the king of Goguryeo, dies suddenly. Woo Hui becomes the target of princes and the 5 tribes who all want to gain more power. To protect her family and her tribe, she uses levirate marriage. She struggles to marry one of her late husband's younger brothers and set them upon the throne. Woo Hui has to accomplish everything within 24 hours.
(Source: AsianWiki)