"Ant-Man and the Wasp: Quantumania" kicks off Marvel's Phase 5 with the return of Paul Rudd and Evangeline Lilly as the titular tiny heroes. When the team accidentally opens up the quantum realm, they end up facing off with Jonathan Majors's Kang the Conqueror, who'll turn into the MCU's next major villain. Fans met a version of the character in the first season of "Loki."