I'm always confused with the electronic/dance music peeps who get guest artists to provide vocals. But I guess figuring that out isn't super hard with the Wikipedias and whatnots.
So this is Disclosure, the band, with Eliza Doolittle (no relation) the singer being the singing person.
I'll tell them you said hey.
Song: "You & Me"
Artist: Disclosure/Eliza Doolittle