Sam Smith Wins the Oscar for Best Song

— -- The Oscars may celebrate the best in film, but some of the music industry's biggest stars were also in the spotlight Sunday night when they performed their Oscar-nominated songs.

First up was this year's Golden Globe winner for best song, Sam Smith, who took the stage solo for a sultry performance of his hit song "Writing's On the Wall," from the James Bond film "Spectre."

He was followed by The Weeknd, who performed his song "Earned It" from "Fifty Shades of Grey." Joined on stage by a group of violin players and female dancers, including an acrobat suspended from ropes, the R&B singer demonstrated why he recently earned two Grammy Awards.

But it was Lady Gaga's performance that was the moment of the night. Introduced by Vice President Joe Biden, the singer gave a powerful performance of her song "Til It Happens to You" from the documentary "The Hunting Ground." She was joined on stage by survivors of sexual assault and at the end of the song joined hands with them, bringing the audience to their feet.

While she received the biggest applause, it was Smith who ultimately won the Oscar.

Accepting the Academy Award, which he dedicated to the LGBTQ community, Smith said he was a "proud gay man."