Jonny Greenwood on BBC Radio 2

Jonny Greenwood and the conductor Robert Ziegler are at Abbey Road recording his score for Paul Thomas Anderson's Inherent Vice when Mark Kermode drops in for Radio 2. It began, Greenwood says, when Anderson put fan bootlegs of his classical pieces against footage, then wrote asking for more music like it for There Will Be Blood. Greenwood had never written for film and saw a chance to get into a studio with an orchestra. Most directors put someone else's music against the film and ask for a close copy of it. Anderson even cuts parts of the film to the music, “which is just absurd and so the wrong way around”, so much of it was recorded without being timed to the picture, and no one knew where it would go; it was written about a character or the scenery.

Writing for film is a collaboration, a bit like being in a band. For There Will Be Blood, beside music written to what was on the screen, he wrote small chamber pieces about a father's relationship with his son in the film, looking for something hopeful in the story. Ziegler reads the scores and shows him what an orchestra can do; on “Future Markets”, a There Will Be Blood cue, he told Greenwood the basses could play it twice as fast. Ziegler describes violinists strumming with guitar picks, their instruments held sideways, for a sound you cannot place, and says Anderson will often keep an early demo of Greenwood's in the cut, then have it recorded again with the orchestra.