Adrian Grenier, Heather Graham and more celebrate next month's Tribeca Film Festival; Gerard Butler, Aaron Eckhart, Ashley Judd and Morgan Freeman hit the red carpet at the premiere of Olympus Has Fallen; Emilia Clarke, Peter Dinklage, Lena Headey and other stars of HBO's "Game of Thrones" step out for the Season 3 premiere; Ryan Seacrest, Emmy Rossum, Nikki Reed and more join Justin Timberlakee at his 20/20 album release party—Monday was buzzing with star-studded events and we have the rundown on them all in this installment of Last Night's Parties.