Williams, whose ubiquitous hit "Happy" has taken the world by storm and spawned copycat dance videos around the globe, worked his magic on the audience at the Montreux Jazz Festival in Switzerland late Monday.
When Williams, wearing jeans, a white t-shirt hidden behind a mass of gold chains and of course his signatory hat, wrapped up the show with his planetary hit, the crowd danced and clapped in unison under a sea of selfie-snapping smart phones.
The boyish 41-year-old told AFP before the concert he could never have imagined "Happy", made for the soundtrack of the film "Despicable Me 2", would be such a hit.
"It was humbling… I couldn't believe anything that I ever did could get that kind of attention," he said.
Creating the unique sound of concentrated carefree bliss that has shot him to solo superstardom was no easy task, he acknowledged.
He wrote nine different songs for a key scene in the movie before coming up with the funky, neo soul song that has gotten the world dancing.
"It was a crazy feeling," Williams said of the response and the multitudes of re-interpretations of the song.
"That's the magical part of it… Everyone has their own interpretation of it," he said insisting "their videos are all so much better than mine".
Williams said he felt "blessed to be able to see … a lot of people's feelings, and you know, them dancing with no inhibitions. Just being joyous."
In Montreux, the R&B, hiphop star also widely known as just Pharrell, seemed intent on spreading the joy further.
"I want you guys to let loose!" he shouted.
Surrounded by a cast of beautiful dancers, twirling and gyrating with inexhaustible energy, the singer, songwriter, producer and fashion designer performed songs from his second solo album "Girl", including the opening track "Marilyn Monroe" — his homage to beautiful women.
'Year of the woman'
"2014 is the year of the woman!" he shouted, briefly halting the music to urge the crowd to fight for gender equality.
He also swept through an array of hits he has produced for others over his more than two-decade career, including Snoop Dogg's "Drop it like it's hot," and Gwen Stefani's "Hollaback girls", before warming to the grand finale with "Blurred Lines", which he produced for and has performed with Robin Thicke, and Daft Punk's mega-hit "Get Lucky".
Throughout, Williams connected with the audience, kneeling down to shake hands with people in the front row, and even snapping a selfie of himself with the audience in the background.
And as "Get Lucky" got started, he pulled a woman who said her name was Silada onto the stage to dance.
After rocking together through the song, Williams urged her to stay on the stage and dance to "Happy" with him.
"We're depending on girls like you to go out and change the world, just so you know," he said, giving her a hug.
"He is really, really sweet. ," gushed Arelle Pinget, 25, after the concert.
"I love that he is so human."
Elaine Hart — one of many donning large hats in honour of Williams — also said she loved the show.
"It was just fantastic!" the 31-year-old British citizen told AFP.
Others however reiterated previous criticism of Williams' 60-minute show.
"The rhythm was amazing," said Christophe Passer, who has written a book about Williams.
"But it didn't last long enough," said Passer.
"It was too short."