Ansel Elgort Theodore Decker Oakes Fegley Young Theodore Decker Aneurin Barnard Boris Pavlikovsky Finn Wolfhard Young Boris Pavlikovsky Sarah Paulson Xandra Luke Wilson Larry Decker Jeffrey Wright James 'Hobie' Hobart Nicole Kidman Samantha Barbour Ashleigh Cummings Pippa Willa Fitzgerald Kitsey Barbour Denis O'Hare Lucius Reeve Luke Kleintank Platt Barbour Peter Jacobson Mr. Silver Aimee Laurence Young Pippa Nicky Torchia Young Tom Cable Robert Joy Welton 'Welty' Blackwell Joey Slotnick Dave Caroline Day Em Pamela Dunlap Mrs. Vogel Misha Osherovich Shirley T Jack DiFalco Young Platt Barbour Aidan Kennedy Middle School Student Alton Fitzgerald White Social Worker Kevin D. McGee Doorman Hannah Kurczeski Middle School Student