Jennifer Garner and Mark Ruffalo Reunite With 'Thriller' Dance for '13 Going on 30' Anniversary

Jennifer Garner, Mark Ruffalo and Judy Greer reunite in honor of the 20th anniversary of their film, '13 Going on 30.' The stars get together in a video posted to Instagram to reminisce about their blockbuster rom-com, including a Michael Jackson 'Thriller'-inspired dance break! The actors break down iconic scenes from the movie, and reflect on how times have changed 20 years later.