05/23/2013 at 09:00 AM EDT
stepped out solo Wednesday night to mingle with an impressive crowd of A-listers – but he didn't forget his fans, either.
Showing his new zombie thriller World War Z
for the first time, hehosted a star-packed screening at New York City's Museum of Modern Art – then zipped to Hoboken, N.J., where he surprised moviegoers at a late-night sneak preview.
"They said we got to do a showing in the city and I said okay, but we can't do it without showing it to the people who we made the film for," he told the Jersey fans. "So we decided to do it than no other place than Jersey. We've got a monster film, it's epic, scary as hell and I guarantee it's the most intense thing you will see all summer."
Back in Manhattan, the VIP crowd seemed to agree. Pals Julianna Marguiles and Kyra Sedgwick joked about how terrifying the movie's hordes of zombies were as they headed with Sedgwick's husband Kevin Bacon to the afterparty at the "21" Club, where Pitt, looking happy and relaxed two weeks after fiancée Angelina Jolie
of her preventive double mastectomy
, mingled with guests.
At the MOMA screening, where he was all in black (pants, jacket and boots), with his hair pulled into a ponytail, Pitt was introduced by Paramount head Brad Grey.
On stage, the star told the crowd, "Thank you. Thank you all very much. We've been on this thing for so long and it's so nice to see friends out in the audience and so many others that I admire who are here tonight – I'm a little big shy about it. So thank you very much. It means a lot to us that you would give up your night for us."
At the party, there were Bruce Willis
with wife Emma Heming, as well as Morgan Freeman and Ashley Olsen
, among others. Katie Couric hugged her former Today
colleague Bryant Gumbel and commented as he walked away, "just like old times!"
Sting and Trudie Styler worked the room, sneaking in some sweet PDA when they reunited after chatting with other pals.
Next up for Pitt is World War Z
's official world premiere in London on June 2. The movie hits theaters on June 21.