The Harry Potterseries has a happy ending, in part, thanks to Narcissa Malfoy, but the books and movies don't get too explicit about why Draco's mother lies to Voldemort and saves Harry's life.

Fiennes-Tiffin taking on the role of Lord Voldemort would be a special twist of fate, considering he is the nephew of Ralph Fiennes, who played the Harry Potter villain in the movies. However ...