The dark knight [sound recording] : original motion picture soundtrack / music composed by Hans Zimmer and James Newton Howard.

Enhanced descriptions from Syndetics:

Even high-budget Hollywood movies generally get by with one A-list composer, but the renewed Batman series that kicked off with Batman Begins under the direction of Christopher Nolan in 2005 used two, Hans Zimmer and James Newton Howard, both of whom return for the second installment, The Dark Knight. Although Zimmer and Howard are co-credited with each of the cues (with Lorne Balfe given a credit for unspecified "additional music"), their styles are sufficiently distinct that their individual contributions don't seem hard to delineate. The highly percussive synthesized music, much of it seemingly already mixed in with sound effects, sounds like Zimmer; the more conventional orchestral passages, sometimes giving way to solo piano, sound like Howard (who is, in fact, credited with playing piano on the soundtrack). Both approaches are combined in these sometimes lengthy cues, however. Those pounding, thunderous drums (or synthesized percussive effects) are never absent for long, even if certain tracks, notably "Harvey Two-Face," "Blood on My Hands," and "Watch the World Burn," have a pastoral, classical feel. Other tracks, such as "I'm Not a Hero" and "A Little Push," in which the percussion dominates, may be more Zimmer than Howard. Still, the two work well together on a score that, by definition, is "dark," laden with ominous sounds and relentlessly rhythmic accompaniments to the fast-paced action in the film. ~ William Ruhlmann