He may fuse African or uber ethnic patterns, fabrics or techniques with western finish and hedonism, but what comes out of Williamson's mind does not feel "sampled" but the fruit of an elusive imagination.
Whether pizzazz on the plage georgette camisoles or sequined bikinis or flip geometric beaded mini dresses, the clothes had great sex appeal, without ever being vulgar.
Prince's dance duo had ignited the mood with their hair shaking, hip swaying, foot tapping fashion moment, the best dancing any of us are ever likely to see on any runway, before the man from Minneapolis, mike in hand, top-hatted, left his front row seat to lead his band in one soaring number.
The collection that followed was Williamson's best in years, with echoes of the ambition of America and the sensuality of Italy, scene of the designer's successful night job at Pucci.
It helped that this show was also a lesson in styling, where Kate Phelan's astute edit gave the clothes a relaxed credibility they had lacked, and kept the bags to a minimum - though the posh punk sacks we saw were easily London's best. Kicked on by a natty soundtrack by DJ Michel Gaubert featuring lots of M.I.A., Williamson won himself a standing ovation.