Marvel's Eternals star Kit Harington knows nothing about his role in future installments of the Marvel Cinematic Universe, saying "nothing is certain." What is certain: the Game of Thrones star makes his MCU debut as the human Dane Whitman, whose comic book counterpart wields the cursed Ebony Blade of medieval legend to become the Black Knight. In Eternals, opening only in theaters on November 5, Dane is the romantic partner of the superpowered and immortal Sersi (Gemma Chan), but not yet an armored Avenger at risk of being driven mad by the magical powers of his blackened blade.