When she got her call with Peyton Reed, Kathryn just knew. "Ant-Man and the Wasp: Quantumania" star Kathryn Newton discusses the entire process of stepping into the shoes of Cassie Lang for the MCU movie. From studying previous comics and films to receiving Marvel tips from Paul Rudd and Jonathan Majors on set, Kathryn spills all on how she gets in (and out) of character.