Stars stepped out last night in NYC to attend The Metropolitan Opera's Gala Premiere of Jules Massenet's Manon, sponsored by Yves Saint Laurent.

OK! GALLERY: TWILIGHT GODDESSES KRISTEN STEWART & ASHLEY GREENE GO GLAM AT THE MET INSTITUTE COSTUME GALA  

Mad Men's January Jones walked the carpet, along with Emma Roberts, Amber Heard, Chloë Moretz, Emmy Rossum, Barbara Walters, Patricia Clarkson and Christine Baranski. 

OK! GALLERY: MAD MEN CAST RINGS THE OPENING BELL AT THE NEW YORK STOCK EXCHANGE 

January wore a gorgeous, long-sleeved black gown, while Emmy wowed in a bright purple, strapless dress.