The chamber was packed, the public gallery was overflowing, stewards were turning journalists away from a jammed press section and MPs were peering in from the corridor as Jeremy Corbyn took on David Cameron in one of the most eagerly awaited Prime Minister's Questions in history.
Promising to deliver a new kind of politics, Mr Corbyn dedicated all six of his questions to the list of suggestions sent in by members of the public.
He was widely-praised for changing the atmosphere in the Commons and gave hope to the growing chorus of voices calling for a reform of PMQs.
Here are 12 things we learned from Mr Corbyn's first exchange with Mr Cameron:
1. The new politics lasted 11 minutes before it descended into the same old baying
Reading out the names of the people who asked questions - Marie, Stephen, Paul, Claire, Gail and Angela – the crowd-sourced questions succeeded in generating a more civilised approach by Mr Cameron and fellow MPs, who temporarily put their heckling and animal noises to one side.
But once the exchange between the two party leaders was over, the baying returned, as Mr Cameron accused the SNP's Angus Robertson of being "frit".
It sparked Mr Robertson to joke: "Whatever happened to new style of PMQs?"
2. Turns out Corbyn knows what he’s doing - he wasn't a complete disaster
He has had a rocky first four days in the job, leading many Labour MPs to fear the worst in his PMQs debut, but clips of Mr Corbyn changing the style of the Commons will be shown on TV screens up and down the country, which can't be a bad thing for the embattled Labour leader.
3. Maybe Labour isn’t quite as divided as you think - Liz Kendall and Corbyn shared a warm hug at the end
Blairite leadership rival Liz Kendall is one of Mr Corbyn's fiercest opponents in the Labour party. She was hurt during the campaign after Corbyn supporters accused her of being a 'Tory'. Images of the pair hugging may help repair relations in a bitterly divided parliamentary party.
On the other hand, being seen hugging the 'Tory' Kendall might land Corbyn in trouble himself with the militant left on Twitter...
4. We know know what the Tory attack line is going to be. You can’t do anything about anything unless you have a strong economy.
As Mr Corbyn grilled the Prime Minister on the Government's poor record on house building, public sector pay freezes, welfare cuts and fears of NHS privatisation, Mr Cameron trotted out the same old line that the Tories provide the "strong economy" that is needed above all else.
5. We know that the SNP are going to keep banging on about the independence and ‘that’ front page.
The SNP's Westminster leader Angus Robertson dedicated his questioning to the Prime Minister's apparent failure to deliver on the cross-party promise to deliver more powers to Scotland - laid out in 'The Vow' on the eve of last September's Scottish independence referendum.
6. There’s a rhino named after Cameron’s daughter
The PM was asked by Tory MP Andrew Turner to intervene to help tiger to be transferred to the Isle of Wight Zoo. Agreeing, Mr Cameron remarked that he had previously helped Cotswold Wildlife Park bring in a rhino, which had then been called Nancy after his daughter.
7. David Cameron will steer clear of personal attacks on Corbyn but won't spare his mates
The Prime Minister left out personal attacks from his first head-to-head with the new Labour leader, complying with Corbyn's request for a new approach to PMQs.
Instead he saved it for Corbyn's right-hand man Mr McDonnell - a controversial choice for shadow chancellor - saying he should be "ashamed" of himself for praising members of the IRA for their role in the armed struggle.
8. A conversational style lowers the temperature
There was definitely less shouting. The new Labour leader asked a series of questions sent to him by named individuals, on housing, rents, tax credits, benefit thresholds and mental health. He did not get personal, and received similarly restrained responses from Mr Cameron.
9. The Prime Minister appeared perfectly happy with the new style.
Mr Cameron said "no-one would be happier than me" if the sessions could be toned down. And he was able to deploy stock answers to the questions, helped by the fact that Mr Corbyn moved quickly on to another subject.
10. Cameron didn't bother with his notes.
The PM usually has a thick folder that he turns to when detailed responses are required - but this time it was tucked away off the despatch box. He only produced it after the Labour leader had finished his six questions.
11. John McDonnell kept a low profile
The shadow chancellor sat quite some distance away from his close friend Mr Corbyn, and appeared to leave early. But his presence was still felt, with DUP leader Nigel Dodds condemning him for suggesting IRA members should be "honoured for their bravery".
Mr Cameron replied that IRA terrorism was "never justified and people who seek to justify it should be ashamed of themselves".
12. John Bercow barely featured
The Speaker usually berates MPs repeatedly for their rowdiness during the 30-minute session. This time his only interventions were to call the next question.
Additional reporting by PAReuse content