Jon Hamm's bringing a lot of joy this morning, with news that he's joining the cast of in a key role.ET can confirm that the and star is set to portray Paul Marks, a corporate titan who sets his sights on United Broadcast Association, pulling network president Cory Ellison (Billy Crudup) and anchors Alex Levy (Jennifer Aniston) and Bradley Jackson (Reese Witherspoon) into his powerful orbit. Production for season 3 is set to begin later this month.The acclaimed Apple TV+ series earned three Emmy nominations: Outstanding Lead Actress in a Drama Series for Witherspoon, Outstanding Supporting Actor in a Drama Series for Crudup and Outstanding Guest Actress in a Drama Series for Marcia Gay Harden.is executive produced by Witherspoon, Aniston, Mimi Leder and Michael Ellenberg.