The shivering performance - which took place on the tucked-away Piano Stage - saw Sumney conjure titanic waves of emotion using the bare essentials - vocals and guitars (plus some sax flourishes for good measure) - and wow the hushed crowd with aplomb.
The impromptu four-track set included Sumney's new song "Indulge Me" ("it's out on Tuesday," Sumney reveals to the crowd), a pared-back rendition of Björk's 1993 single "Come To Me" - which you can watch above - as well as fan favourite "Plastic".
"Come To Me" (Björk cover)
"Plastic" (with Nick Hakim)
"Green Twins" (Nick Hakim featuring Moses Sumney)