Four glorious golds for Grace Harvey, Brock Whiston, Maisie Summers-Newton and the Mixed S14 4x100m Freestyle Relay team, plus a bronze for Alice Tai, ensured Britain's para-swimmers played a crucial role in ParalympicsGB's most successful single day at a Games this century.
In what is becoming an increasingly outstanding meet for the Aquatics GB cohort, that quartet of Paralympic titles - capped by a stunning triumph for Will Ellard, Rhys Darbey, Poppy Maskill and Olivia Newman-Baronius in that mixed freestyle relay - contributed to an incredible 12 golds won across all sports on the day by the GB team, while the swimmers are now up to 11 golds and 16 medals overall after four days.
There were headlines wherever you looked in the pool, with the quality of the team summed up by the fact that the night opened with stalwart Summers-Newton completing the 'double double' of her Paralympic titles across Tokyo and Paris after triumph in the Women's SB6 100m Breaststroke, and then ended with a quartet of four Paralympic debutants storming to relay victory.
In between that, there were maiden Paralympic golds for Whiston and Harvey, the former in a dramatic Women's SM8 200m Individual Medley final.
Tai - a gold medallist in the S8 100m Backstroke a mere 24 hours before - was the dominant early leader in this race, with Whiston sat sixth at the halfway point after the butterfly and backstroke legs. But Brock is a breaststroke specialist, and she was driven by just missing out on gold in the SB8 100m Breaststroke final earlier in the week across a storming 50m of breaststroke in this showpiece, moving her to within 0.13s of Tai at the final turn.
From there, it was down to an incredible freestyle finish between the two Brits and Viktoriia Ishchiulova in between them. Whiston and Ishchiulova looked destined to touch in tandem, only for Brock to find an extra burst in the final five metres to get to the wall first and claim her maiden Paralympic gold, with Tai just behind for bronze.
"I had something to prove to myself, I wanted to come out and show what I can do, and I think I did that tonight, nothing was stopping me from doing that. It wasn't how I expected to race, but I'm really happy with the outcome, I'm buzzing," she said, reflecting after a great swim but near-miss in the breaststroke event two days before.
"That [bouncing back] is what you have to do as an athlete, you're going to have good swims and bad swims, and you have to bounce back from the bad ones to really show what you've trained to do. I am really happy with that performance."
Bronze medallist Tai - who has now reached the podium in two finals from two so far in Paris - added: "I am really happy with my performance, it's always going to be a little bittersweet when it's so, so close at the end. We have so many debutants on the team this year, and all of them are swimming amazingly. It's so cool to just see what the next few years of para-swimming for Great Britain are going to bring, and Brock is part of that, it's so cool."
Whiston's first Paralympic title triumph was mirrored by Harvey a short while afterwards, in another nip-and-tuck final of the Women's SB5 100m Breaststroke.
A silver medallist three years ago in Tokyo, Grace stuck admirably to her race plan in the centre lane, with Ukraine's Anna Hontar and Li Zhang of China going out hard either side of her across the opening lap.
Sitting third at the turn, the Aquatics GB Manchester Performance Centre swimmer trusted in a well-executed turn and her back-end speed to see her home, and with Hontar dropping back, she clawed back to be level with Zhang heading into the final strokes. Like Whiston, she was not to be denied, powering into the wall for the gold.
"It means more than anything. I've never dared imagine that I'd be in this position, I just wanted to go out and do my own race - but to finally finish first, it feels amazing! I've never been that person that says 'I want to be Paralympic champion', it always felt like that unattainable goal, so to actually come away first, I'm like 'wow, this is my moment and all that hard work has really paid off'," said Grace.
"La Defense Arena and the crowd here just really raise the noise for everyone. We have such a strong team, our qualifying times are some of the hardest in the world - we are here to perform, to showcase our talent to the world and we are doing that."
A fourth Paralympic title of her career was no less special for Maisie Summers-Newton to open the evening for ParalympicsGB. Fresh from defending her SM6 200m Individual Medley crown on Friday, the Northampton Swimming Club star was again always in control here in the SB5 100m Breaststroke finale, maintaining an unbeaten record in this event at major meets since 2019 and setting a new Paralympic record of 1:31.30.
"I'm so chuffed, my nerves were on a different plane compared to the 200m IM. I just went in trying to enjoy the whole moment, I know my breaststroke is my strongest stroke. I got in, loved it, the crowd was amazing - and to defend both my titles, I couldn't have asked for much more," said Maisie.
"It's crazy! Thinking back to when I was watching Ellie Simmonds in London 2012, never would I have thought I'd come away with four gold medals from two Paralympics, let alone even one. I'm so happy, and to do it in front of my family, to get on that podium again tonight, it's just fantastic."
The fourth and final gold of another awe-inspiring day at La Defense Arena for ParalympicsGB came courtesy of Ellard, Darbey, Maskill and Newman-Baronius in the Mixed S14 4x100m Freestyle Relay.
Remarkably, this victory meant a defence of the title won in Tokyo by Great Britain, but by an entirely new relay quartet - and with all four making their debuts in Paris.
Ellard, a day on from his world-record-breaking S14 200m Freestyle victory, set the tone with a strong opening leg to give GB a lead that Darbey, in his first race of these Games, engaged in a fierce battle with the Brazilian team one lane up to keep Britain in the lead.
It was then over to 200m Freestyle champion Maskill to lay down arguably the leg of the final to build a near-five-second lead, which Newman-Baronius swam brilliantly to defend emphatically on the anchor to bring home the crown.
"It's amazing. We are all pretty young and all our first time at a Paralympics, that's pretty cool and for us to do that. I don't think about other racers, we just try our hardest and see how we go," said Maskill afterwards.
Darbey added: "I was definitely trying to make as much room as I could for Poppy after me, and then look to hold the lead the best we could. I think we did a pretty good job of that and I'm pretty happy with the swim as well, so it's all good!"
Away from the podium, there were more strong swims for the GB cohort. Callie-Ann Warrington played her part in a brilliant Women's S10 100m Freestyle final, setting a new British S10 record of 1:01.10 to finish a mere 0.08s off the podium in her first Paralympic final. Faye Rogers came close to reaching the final too, missing out after a swim-off following a dead-heat in the heats.
Bruce Dee, meanwhile, was fifth after another controlled effort on his Paralympic debut in the Men's SB6 100m Breaststroke finale.
