Miles Wingrave

Miles is the young master of Bly Manor, freshly sent home from boarding school under a cloud nobody will explain. He greets the new au pair with a handshake and unnerving formality, all charm and old-fashioned manners, while something flickers underneath that suggests he's carrying more than a small boy should.

Benjamin Evan Ainsworth plays childhood as performance, all borrowed adult phrasing and too-steady eye contact, so the wrongness announces itself before the plot does. It's a genuinely difficult role, asking a kid actor to be sweet and quietly terrifying in the same breath, and he never once tips his hand.