Oscar Nominee Alicia Vikander and More Actors Let Loose with Sam Smith at a Pre-Awards Show Celebration 

After an early day of press at the Oscars Nominee Luncheon Monday, it was time for the stars to let loose at The Hollywood Reporter’s annual Oscar Nominees Night bash.

Alicia Vikander and Jennifer Jason Leigh (below) were among nominees in attendance at the event at Spago in Beverly Hills, Calif., with the Danish Girl star hanging out with friends in a strapless black pantsuit with a glass of red wine in hand. As they chatted and posed for selfies, Topher Grace munched on a plate of grub at a nearby table filled with pals.

Guests made sure to get their fill of the decadent spread at the bash as well, with servers spooning and forking helpings of jidori chicken breast, roast beef, cheesy mashed potatoes, stuffed pasta, roasted cauliflower and more on plates. Partygoers also satiated their appetites at a sushi station topped with spicy tuna rolls, and with mini cheeseburgers and spicy tuna cones that waiters were passing out.

To wash all of that down, they headed to a posh open bar topped with white flowers, grabbing bottles of Fiji water and sipping Woodford Reserve cocktails as well.

While a DJ kept people on their feet with hip hop and top 40 hits, Sylvester Stallone (below) and Piers Morgan strayed away from the dance floor and greeted each other ahead of surprise performer Sam Smith’s mini concert instead.

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When Smith hopped on stage looking dapper in a black suit, he kicked off his intimate performance with “I’m Not the Only One.” While he crooned the lyrics, guests sang along with him and when he finished up he said, “I'm going to sing a few songs if that's okay,” as the audience erupted in cheers. “This is the first time I've sung in like two months,” he continued. “Feels really good.”

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The singer said with a smile that he was at the event for a “special reason,” noting with a smile that his song “Writing’s On the Wall” had been nominated for an Oscar. Then, fittingly, he sang the song next, before making guests swoon with a performance of “Stay With Me."