Stellar displays from Britain's Mo Farah, Dai Greene and Phillips Idowu lit up a wet evening in Birmingham as Asafa Powell won the 100m.
Farah ran 13:06.14 in the 5,000m after Idowu leapt 17.54m to beat an under-par Teddy Tamgho in the triple jump.
Meanwhile, Greene's impressive 48.20 in the 400m hurdles defeated former world champion Bershawn Jackson.
Powell, fastest man in the world this year, sprinted to victory in 9.91 ahead of fellow Jamaican Nesta Carter.
"People have questioned me about my move to the United States but as an athlete you've always got to be looking at how to improve yourself and what you can do better," Farah said.
"You have to be prepared to cover every move in a race and you have to get it right on the day - the gym work has made me stronger and the speed work faster, so it's all been worth it."
The three Britons confirmed their class and form ahead of the World Championships in August, leaving their big-name rivals trailing as rain failed to dampen the UK's first Diamond League meeting of the summer.
Farah, 28, produced a 54-second last lap to blow the 5,000m field apart, while Greene's battling 400m hurdles win pushed him to the top of the event's Diamond Race standings.
Powell, the hot favourite in the absence of the injured Tyson Gay, overcame a slow start to race to victory.
Farah has been in scintillating form since his move to Oregon to work with innovative coach Alberto Salazar, smashing the European 10,000m record last month, and he ran a perfect tactical race to comprehensively beat both training partner Galen Rupp and Ethiopia's Imane Merga.
Keeping close order when the race began to hot up with 800m to go, Farah hit the front at the bell and wound it up down the back straight before kicking again to win in dominant fashion.
Having won European 10,000m and 5,000m gold last summer he now has a real chance of matching at least one of those medals on the global stage.
Greene can also now be considered a genuine contender for gold at the Worlds in Daegu, South Korea after holding off Jackson and Javier Culson for his second big Diamond League victory in a fortnight.
The European and Commonwealth champion led coming into the home straight and dug deep to keep the fast-finishing Jackson at bay to clock a season's best time.
His 19-year-old training partner Jack Green produced a personal best of 48.98 to take fourth and confirm his substantial potential in his first senior season.
Greene also beat the stadium record of the greatest one-lap hurdler of them all, Ed Moses - something which will give the Welshman, who wrote his 10,000-word university thesis about 400m hurdling, great pleasure.
He said: "I was so happy to win and get a season's best in such horrible conditions. It's only the second time I've ever beaten Bershawn - I need to be competitive with these guys, and I'm at the top at the moment."
Tamgho - world indoor champion and record holder - has out-jumped Idowu's best ever mark on six occasions, most recently with his huge 17.91m in Lausanne a fortnight ago.
But Britain's reigning world and European champion produced a jump of 17.54m in the third round as Tamgho no-jumped three times and failed to get close to 17m in his three attempts that were legal.
"It was a funny competition today," said Idowu, who extended his lead in head-to-head contests with the young Frenchman to 7-3. "For me the main thing is that I'm consistent. In pretty much all my competitions this year I've been around 17.50m so it looks good - if I am consistent around the time of the Worlds then hopefully I can find another 15cm."
Powell kept his head while others lost theirs on the blocks - Norway's Jaysuma Saidy Ndure false-starting and Michael Rogers pulling out just before the gun with injury - to come through comfortably from his Jamaican compatriots Carter (9.93, with a following wind of 0.4m/s) and Michael Frater (10.01).
He said: "It was cold out there so I didn't push it from the start. I was only going to do enough to win today, but at the Worlds I'm definitely going to win. I'm going for it and I'll try not to disappoint."
Sally Pearson set a world-leading time of 12.48 to smash the Australian and British all-comers' record in the 100m hurdles.
"I need to find my coach and ask, what now?" she said afterwards, putting behind her the disappointment of disqualification after winning Commonwealth gold last October. "I've always wanted to be the best in the world, and I'm heading in that direction."
Double Olympic champion Andreas Thorkildsen was another to set a world-leading mark with a throw of 88.30m to win the javelin in difficult, damp conditions, underlining his position as favourite for another world title next month.
But reigning 400m world champion Sanya Richards-Ross endured another difficult race as she returns from injury, way down in fourth behind Botswana's Commonwealth champion Amantle Montsho.
World high jump champion Blanca Vlasic has also not been at her very best this season, and she secured victory over Anna Chicherova only on count-back after clearing 1.99m on her second attempt to her Russian rival's third.
Abubaker Kaki took the men's 800m in 1:44.54, while Britain's Jenny Meadows clocked 2:02.06 beat a largely domestic field in a non-Diamond League women's 800m.
British tyro Holly Bleasdale gave the sell-out crowd of 13,000 further reason for optimism by following up her recent national pole vault record with an excellent 4.61m for second place behind the vastly more experienced Silke Spiegelburg.