Amanda Seyfried [1] and Justin Long [2] stepped out for a rare public appearance at the Costume Institute Gala at the Metropolitan Museum of Art in NYC on Monday night. Amanda, who wore a white Givenchy gown, was all smiles while posing for photos with Justin on the red carpet. The extravagant event is a far cry from the couple's normal routine. Amanda and Justin, who started dating nearly two years ago [3], are normally seen being goofy with each other [4] during casual outings. Keep reading to see more photos of their adorable night out, then check out all the celebrity arrivals [5] at the Met Gala.