Celebrity Al Pacino, Christopher Walken & Alan Arkin Are 'Stand Up Guys' in N.Y.C. By People Staff Published on December 9, 2012 12:45 PM Share Tweet Pin Email Photo: Marion Curtis/StarTraks It was an A-list party for the A-listers! On Sunday night, Al Pacino, Christopher Walken, Alan Arkin and Julianna Margulies celebrated their new film Stand Up Guys at The Oak Room in New York’s Plaza Hotel. “Al Pacino chatted with Christopher Walken, Alan Arkin and director Fisher Stevens as they sipped on cocktails,” an onlooker tells PEOPLE. It was a star-studded affair as Ben Stiller, Liev Schreiber, Matt Dillion, Jeremy Piven, Mariska Hargitay, Jon Bon Jovi, Alan Cumming, Girls‘ Zosia Mamet and Boardwalk Empire‘s Bobby Cannavale were all also in attendance. After the screening at the Museum of Modern Art ended, guests enjoyed Appleton Estate cocktails, small bites of lobster claw, salmon tartar, mushroom crostinis and shrimp cocktails.– Melody Chiu NEXT: Martha Stewart Hits Miami for Art Basel Party