Maisie Williams came with her Daisie app cofounder Dom Santry.
Williams, better known as Arya Stark on "Game of Thrones," was 90th on the Tech 100 list after she launched her anti-nepotism app Daisie with cofounder Dom Santry.
Guests including journalist Carole Cadwalladr climbed the stairs to the top of The Gherkin.
Cadwalladr was 19th on the list after exposing Facebook's Cambridge Analytica data scandal.
The setting was pretty spectacular, and guests were served drinks from an old vintage motorcycle.
And if the bubbly wasn't enough to make guests dizzy, some tried walking off a plank in VR.
The Tech 100 list was up in lights.
London Mayor Sadiq Khan came 40th on the list, and gave a speech.
He made a joke at Prime Minister Theresa May's expense: "We have had over the last 12 months this amazing technology which is an entire prime minister's speech being delivered by a robot and nobody notices."
Khan also stopped for a chat with BI UK Editor-in-Chief Jim Edwards.
Khan wasn't the only politician in the room, Conservative MP Damian Collins also stopped by after coming 80th in the ranking.
Phoebe Hugh from AI-powered insurance aggregation company Brolly. She was 58th in the Tech 100.
Here's the man behind Monzo, Tom Blomfield — number eight in the Tech 100.
Cryptocurrency specialist Joon Ian Wong (66th) came along...
...as did AI researcher Dr Catherine Breslin (42nd), the woman teaching Alexa for Amazon.
Emoji maestro Jeremy Burge (76th) and podcast don Myke Hurley (59th) were all smiles.
As was Live Better With founder Tamara Rajah (72nd).
Gamer-in-chief of indie gaming studio Bossa, Henrique Olifiers, was 33rd on the list.
Paddle founder Christian Owens (in the middle) came in at number 84.
PatSnap's Ray Chohan was 85th.
The YouTuber with a following over a million strong, Tom Scott (89th).
Blockchain boss Peter Smith (38th) rubbed shoulders with...
...taxi drivers' union champion Steve McNamara (97th).
Some guests stopped for a picture with Business Insider's tech team.
Even Business Insider staff got to let their hair down.
