Golden Globe nominee Sam Smith and host Ricky Gervais were some of the first stars to arrive on the red carpet at the glamorous awards ceremony.
The singer, who is nominated for best original song for his single Writing's On The Wall from the James Bond film Spectre, opted for a classic black tuxedo, while Gervais added a pair of mirrored sunglasses.
Arriving with his girlfriend Jane Fallon, Gervais joked: "I'm heavily sedated under doctor's orders."
Speaking to E!'s Ryan Seacrest, the comedian said his hosting rehearsal featured a string of jokes that he will not be able to tell in the packed ballroom.
He said: "I did it just for fun to get it out of my system. I don't know when I can ever use those jokes."
Gervais added: "Every time I do something like this I'm looking forward to it being over so I can have a little reward, I'm not cut out for this."
Asked by Seacrest if Gervais has a drink before such events, Fallon replied: "Before, during, after."
Gervais is returning to the hosting job for a fourth time but is a controversial choice because of his cutting jokes about the famous faces in attendance.
Actresses Bryce Dallas Howard, Jaimie Alexander and Gina Rodriguez added a touch of glamour to the red carpet proceedings in dramatic gowns.
Rodriguez, who opted for a navy blue Zac Posen gown, is nominated for the best TV comedy actress award for her title role in Jane The Virgin after winning for the same part last year and was joined on the red carpet by her father.
Alexander, who was dressed in a plunging emerald gown by Italian designer Genny, was accompanied by her fiancee Peter Facinelli.
Smith, who was dressed in a Dior tuxedo, arrived on the red carpet with Writing's On The Wall songwriter Jimmy Napes and admitted he was already feeling a little worse for wear.
He told NBC: "I'm actually hungover from last night, I started yesterday. I started like I mean to go on."
Asked if he would be acting up, he replied: "Hell yes! Me and Jimmy are drinking hard."
He added: "This is my first acting thing, I'm just freaking out. There are so many people here I recognise, it's great."
British actor Mark Rylance, who is nominated for both best supporting actor in a film for Bridge Of Spies and best actor in a limited series or TV movie for BBC drama Wolf Hall, added a brown hat to his dark suit.
He said: "It feels lovely to be celebrated. It's my first awards on the west coast. It's a way of encouraging people to see movies and that is a good thing."
Transparent actor Jeffrey Tambor, who is nominated for best TV actor in a comedy, was joined by his co-stars and the show's creator as he arrived at the ceremony.
He said having a food plan was the most important part of the night and whipped a cereal bar out of his pocket as he told NBC: "I have a pound of M&Ms in my left cheek, I'm not joking."
Michael Shannon, nominated for best supporting actor for his role as a real estate tycoon in 99 Homes, arrived on the red carpet in a Prada tux, saying: "This is very unlike where I'm from in Lexington, Kentucky but is maybe closest to the Kentucky Derby but there are no hats."
Alicia Vikander, who is also a double nominee for best supporting actress in a film for Ex Machina and best lead actress in a movie drama for The Danish Girl, triggered a flurry of flashbulbs in a white sequinned Louis Vuitton gown with ruffle details while Mad Max star Rosie Huntington-Whiteley opted for a gold beaded gown.
Brie Larson, who joins Vikander in the lead actress in a drama category for her role in Room, also opted for a gold sequinned gown with cut out panels.
Larson told Seacrest: "It's Calvin Klein and they made it for me. It's heavy but in a great way, it's like I'm in a hug constantly, I don't feel so vulnerable. I feel very protected, like I have Joan of Arc armour on."
She added: "I'm totally cruising right now, I'm totally OK. I spoke to Emma Stone before and she gave me a pep talk and told me I'm going to have the best time because I'm inside the TV."
Michael Fassbender, who is nominated for best lead actor in a dramatic movie for the titular role of Steve Jobs, revealed he had a speech tucked away in his tuxedo pocket.
He told NBC: "I do plan ahead now, I've tended to wing it in the past and that never works out so I've come prepared."
Uzo Abuba, who is nominated for best supporting TV actress in for her role as Suzanne "Crazy Eyes" Warren in Netflix drama Orange Is The New Black said she felt overwhelmed by the occasion.
She told Seacrest: "I feel like if my head wasn't connected to my body it would be rolling on the floor."
She added that the Globes is a particularly fun awards show, saying: "You get to talk with your friends, hang out with your friends, chill, relax and have some champagne."
Joanne Froggatt, who is nominated for best supporting actress in a limited series or TV movie, chose a pale blue Reem Acra gown with a white sheer panel at the front. She told Giuliana Rancic on E!: "I feel really comfortable, it's the second dress I tried on and I just knew."
Amy Schumer, who is nominated for best actress in a comedy or musical, chose a black and white off-the-shoulder gown and told Seacrest she injured her knuckles while boxing the day before the ceremony.
Her fellow nominee Melissa McCarthy, who received a nod for Spy, said: "This is my favourite one, it's like the wedding where you get to see everyone and any time a comedy gets a shout-out I feel really lucky. It's exciting to be here."
Saoirse Ronan, who is nominated in the best actress in a dramatic movie award for Brooklyn, opted for a flowing while gown with a long train, while her fellow nominee Cate Blanchett, who is nominated for Carol, wore a dramatic pink fringed gown.
Lead actor in a drama nominee Will Smith greeted fans on the red carpet with comedian Kevin Hart while Rob Lowe took videos of the screaming fans as he stepped out of his limousine.
Kirsten Dunst, who is nominated for best lead actress in a limited series or TV movie, said: "I was very relaxed at home and I'm pretty chilled right now but I don't know why, it's such a cattle call that you just feel like pretty meat being shoved down this carpet."
Jennifer Lopez, who is presenting at the awards, opted for a mustard Giambattista Valli gown with a thigh-high split and cape. She told Seacrest: "I just loved it, it was so fashion-y and different to anything I've ever done."