The disc's first two tracks, "Future Proof" and "What Your Soul Sings," evoke the profound unease and exposed-nerve emotiveness of Kid A and Amnesiac. Chilled yet expansive, these numbers paradoxically morph psych rock into blissed-out blues. Sinéad O'Connor sings on the latter, and she and reggae fixture Horace Andy do some of their finest vocal work on two more cuts each. But the real treat is the string orchestration that adorns several songs, waxing Middle Eastern like Led Zeppelin's "Kashmir" on downers. And while 100th Window's prevailing hue is midnight blue and its tempo slow as a walk to the electric chair, the artistry of Massive Attack's arrangements and textural soundscaping makes the album as uplifting as a Prozac-and-Red-Bull cocktail.