In a world where magic is outlawed and witches are hunted, socialite Rune Winters secretly acts as the Crimson Moth, a vigilante who rescues her own kind from execution. To gather intelligence on the government's purge, she begins a dangerous game of deception by courting Gideon Sharpe, a notorious and ruthless witch hunter. As their lives become increasingly intertwined, Rune must protect her secret identity while navigating a growing attraction to the man sworn to destroy her.