The soundtrack of the film was written by Howard Blake , and is scored entirely for string orchestra in the style of early 20th Century British music . Blake note that the style chosen was intended to complement and contrast recordings of classical music during particular scenes : Verdi 's Quattro pezzi sacri was used during the uncovering of the mediaeval mural and a flashback montage of the First World War which opened the film utilised an excerpt from Schubert 's Deutsche Messe ( D. 872 ) " Zum Sanctus : Heilig , heilig ist der Herr " .