A birthday to remember! Joined by a star-studded list of pals, including Ben Stiller, Isla Fisher, Sacha Baron Cohen, Dax Shepard and more, Jennifer Aniston feted her fiance Justin Theroux with a memorable 42nd birthday bash at their $21 million Bel Air mansion on Saturday, Aug. 10.
Pre-party, a source tells Us Weekly that the ladies got ready inside (Aniston's hair stylist Chris McMillan was on hand to style the We're The Millers star), while Theroux, an actor-screenwriter, hung out with his guys outside.
"Several of Justin's friends spent the afternoon at the house hanging out by the pool with him and celebrating his birthday," an eyewitness shares. "It was a relaxed afternoon and they were all in the cabana area having drinks and listening to music like Kanye West and The Kinks."
With a catering team preparing an outdoor barbecue buffet, Aniston and her man began to greet the rest of their guests around 7pm, with the pair "making a point to hug everyone that arrived." (Other attendees included Lake Bell, Will Arnett, Laura Dern, Ellen DeGeneres, Portia de Rossi, Tobey Maguire, Jen Meyer, Jimmy Kimmel, John Krasinski, Emily Blunt, and Jason Bateman.)
"Most people were dressed casually in jeans and T-shirts," a source tells Us. "Justin was dressed casually in a black T-shirt and black jeans, and Jen had on a short green skirt and long sleeved top."
While the actress, 44, chatted with her friends, mostly sticking to gal pals Fisher and Meyer, the birthday boy — who received gifts from Cartier and Barney's — spent a majority of the night with Shepard and Kimmel.
At the celebration, which fell on the one-year anniversary of the pair's engagement, guests enjoyed a relaxed and fun atmosphere.
"All of the windows and doors were raised to give the house an indoor outdoor feel," the source shared. "People were admiring the city views as the sun went down. There were candles everywhere and a fire pit was lit."
The couple, who connected while making 2012's Wanderlust, went public with their romance in May 2011.
Sign up now for the Us Weekly newsletter to get breaking celebrity news, hot pics and more delivered straight to your inbox!