Lauren Sanchez shares peek inside Gayle King's star-studded surprise b'day party... and reveals who planned it

Lauren Sánchez revealed that Oprah Winfrey was behind Gayle King's star-studded surprise birthday party.

King, the star personality at CBS News and editor for Oprah Daily, unknowingly walked into an early birthday celebration on Friday evening - two weeks ahead of her 70th birthday on December 28.

The internet got a sneak peek into the night after Sánchez - the 54-year-old former new anchor engaged to Amazon founder Jeff Bezos - shared two posts with her followers on social media.

In a video posted to Sánchez's Instagram Stories, at least 100 people were seen standing side-by-side in a posh lounge as they sang 'happy birthday' to the beloved CBS Mornings co-host.

'Happy surprise birthday @gayleking, @Oprah you pulled it off,' the caption read, accompanied by a smiley face and red heart emoji.

But it wouldn't be a true birthday party without a few tequila shots.

Sánchez captured a photo of a wooden, four-level bar cart topped tequila shots dressed with a lime for the taking.

Behind the 1.5-ounce glasses stood a small cartoon cut-out of King wearing a yellow dress with a martini in hand.

The cartoon King was attached to a little pink banner that read: 'Let's Toast To Gayle!'

Thankfully, Oprah delivered the one moment the internet wanted to see - Gayle unknowingly walking into her own party.

In the video that was shared to Instagram early Saturday afternoon, King can be seen in a teal, three-quarter sleeve maxi dress paired with matching heels as she walked alongside the legendary talk show host, who was wearing a mustard-yellow jumpsuit.

King and Oprah were captured chatting as they headed through the lounge - all while King appeared to be oblivious to the large group of familiar faces just ahead of her.

But a second later, the crowd can be heard loudly screaming 'surprise!' - sending obvious shock waves through the birthday girl.

She was so startled that she dropped her bag on the table next to her while simultaneously taking a few steps back and clutching both hands to her heart.

The party-goers continued cheering for King, whose mouth was still dropped in shock, as she looked around at all the people gathered directly in front of her.

Her arrival prompted the happy birthday song, which prompted an emotional reaction from King who held her hands over her mouth. 

'My bestie of 50 years is turning 70 so we gathered everyone that loved her to celebrate,' Oprah wrote in the caption of the video. 'Hard thing to surprise her.'

'Oh, the stories we have made up, the lies we have told to keep this a secret,' she added. 'Happy birthday @gayleking, sorry we almost gave you a heart attack.'

Earlier this year, Oprah marked the same milestone birthday, despite the celebration being much more low-key.

She spent her winter-season birthday with a jog on the beach - documenting the moment to Instagram where she hash-tagged: #healthisthebestgift.

King celebrated the big day by posting a precious video that captured the mogul spending some quality time with King's grandson during a getaway vacation.

'Happy to say at 70 @oprah is still a very good reader!' King wrote in the caption. 

'While Favorite grandson Luca is too young to understand how special this moment was during Christmas vacation, it's not lost on me.'

'When asked how she wanted to spend her birthday, she said, "No gifts, no parties, no surprises!"', King added.

'Her preference was to sit by the fire with a good book and savor the fragrance of her life! Happy birthday Oprah!'

Little did King know that her bestie would celebrate her birthday with the same things she denied for herself eleven months prior.

It's definitely safe to say that King's 70th birthday will be one that she'll never forget.