He's been on a whirlwind press tour to promote his new flick Friends with Benefits (out today!), but Justin Timberlake joined Amanda Seyfried (in Prabal Gurung) yesterday at Comic-Con in San Diego, California. The duo attended a press conference for their film In Time, a sci-fi thriller set in the future. Click through the gallery to see Kristen Stewart, Ashley Greene, Carey Mulligan and more stars at last night's hottest parties!