"That foreboding sense of dread, though, comes in large part from the score by Radiohead guitarist Jonny Greenwood...Greenwood told EW:
'I think it was about not necessarily just making period music, which very traditionally you would do. But because they were traditional orchestral sounds, I suppose that's what we hoped was a little unsettling, even though you know all the sounds you're hearing are coming from very old technology. You can just do things with the classical orchestra that do unsettle you, that are sort of slightly wrong, that have some kind of undercurrent that's slightly sinister...'"
'Radiohead's Greenwood Goes Sinister for There Will Be Blood'-LA Times