Before his iconic roles in The Avengers and Spotlight, Mark Ruffalo charmed us all in 13 Going on 30, playing Matt, the nerdy and sweet love interest of Jenna, who's played by Jennifer Garner. Thirteen-year-old Jenna wakes up to discover that she's now a head-honcho fashion editor whose glamorous life belies her lack of authentic relationships. That is, until she gets in touch with her former best friend Matt.