My Sister's Secret: The Warrior Queen — Episode 6

Abandoned by their parents, the Blackwood sisters, Katherine and Grace, grew up relying only on each other. As adults, both built successful lives. But Katherine arrives at Grace's engagement party straight from a secret mission, still disguised as a cleaning lady, and becomes the target of ridicule from former classmates and the groom's family. When her sister is betrayed and humiliated by the fiancé, Katherine reveals her true identity as the Warrior Queen, making everyone regret underestimating them.