It's the culmination of months of campaigning and a night when the film industry celebrates while the world watches and marvels at the spectacle.
British hopes are resting on Eddie Redmayne to bring home an Oscar for his portrayal of Stephen Hawking in The Theory of Everything.
Michael Keaton is Redmayne's greatest threat in the race to be crowned Best Actor. He is nominated for his starring role in Birdman.
The Best Actress category boasts two British stars: Rosamund Pike for Gone Girl and Felicity Jones for The Theory of Everything.
But the smart money is undoubtedly on Julianne Moore, who is nominated for her role in Still Alice.
Keira Knightley is nominated for best supporting actress for The Imitation Game, but the prize is likely to go to Patricia Arquette, who stars in Boyhood.
The race is expected to be between Boyhood and Birdman for both Best Picture and Best Director.
Director of Birdman Alejandro Gonzalez Inarritu told Sky News he was feeling very relaxed about the result.
"I feel very lucky," he said.
"We already won. It's a win-win situation now the film has arrived to a place which I never expected. So I'm very thankful and grateful for that."
Also nominated for best picture is Selma. Producer and star Oprah Winfrey says the nomination is down to its British lead David Oyelowo.
"I saw in him some of the same spirit as myself and I wanted to do whatever I could to open that space for him so he could be all he was meant to be," Winfrey said.
"He is just one of the finest human beings I know."
The star of Selma says he is overwhelmed at the film's success.
"I just feel elated that we're there with best picture and best song, and I get to be at this event that I've watched since I was a little boy," Oyelowo said.
"It is a very special time and this is what these awards shows are for - to bring attention, especially to these smaller movies and we have done that in spades and in ways we didn't realise."
Perhaps this year more than most there has been fierce debate over what was nominated and what wasn't, with both American Sniper and Selma proving controversial.
But it's exactly that type of publicity that's making it one of the most talked about shows in the world.
And even for the Academy's most famous members like Zero Dark Thirty star Jessica Chastain, these aren't easy decisions to make.
She said: "It is such a weird thing. I'm a member of the Academy and to vote at the end there is a sense of why can't I vote for more than one - so I have difficulty choosing.
"I love Eddie and Benedict and David Oyelowo - you guys know how to create actors."