Great Britain claimed a fourth swimming gold at an Olympics for the first time in 113 years by winning the inaugural 4x100m mixed medley relay in a world-record time.
The British quartet of Kathleen Dawson, Adam Peaty, James Guy and Anna Hopkin won in three minutes 37.58 seconds.
China took the silver medal while Australia won bronze.
The gold is Peaty's second in Tokyo after the 100m breaststroke while Guy also won the 4x200m freestyle relay.
"One word has changed the whole British team - belief," said Peaty.
"We believe we can win, we believe we can get world records. If you have belief, you can build everything around that and we showed that here."
Great Britain were more than two seconds clear of the field in the heats and continued that dominance in the raceGB stage stunning recovery
The victory was all the more impressive given Dawson slipped off the wall at the start of her backstroke leg before fighting back superbly to give her team-mates the chance to chase down their opponents.
Peaty and Guy overturned the deficit in the middle two splits - the latter completing his 100m in just 50 seconds - before Hopkin held on in a final 100m that featured American superstar Caeleb Dressel.
The USA were surprisingly not much of a factor as they finished fifth, with Dressel left way too much to do in his leg - in what was the 24-year-old's third race of the day.
"I was trying not to think about it [Dressel chasing her down]," said Hopkin. "I was trying not to think about how far ahead we were from them.
"It's just irrelevant when you're in the water - you've just got to race. When I turned I saw I still had a good bit of water in front of me and I just went for it. It's an amazing feeling and a privilege to be in this team."
Great Britain have seven swimming medals so far in Tokyo and could add to that on Sunday with the men's 4x100m medley relay team and Dan Jervis (men's 1500m freestyle) and Ben Proud, who qualified from his 50m freestyle semi-final on Saturday, all in finals action.
Dressel breaks record on way to gold
Earlier, Dressel claimed his third gold medal of the Tokyo Olympics with a world record-breaking swim to win the men's 100m butterfly.
The 24-year-old touched home in 49.45 seconds - although was pushed late on by Kristof Milak of Hungary, who finished just 0.23secs behind. Noe Ponti of Switzerland took the bronze.
USA's Katie Ledecky won the 800m freestyle gold for the third successive Olympics with a dominant swim.
She finished in a time of 8:12.57 as she got the better of Ariarne Titmus, who claimed silver, with Simona Quadarella taking bronze.
Australian Titmus beat Ledecky, who now has six Olympic golds, in the 200m and 400m freestyle.
Finally, Australia's Kaylee McKeown eased to gold in the women's 200m backstroke.
It is McKeown's second gold of the Games after winning the 100m backstroke in a time of 2:04.68. Canada's Kylie Mass took silver with Emily Seebohm of Australia claiming the bronze.
