The second chapter in the Mass Effect trilogy is more of an enigma than the first, weaving enough moral ambiguity, ghost-like images, and misleading plot twists to make the writers of the TV show Lost take note. Who are the Collectors? What interest does the mysterious Illusive Man have in Commander Shepard? Where are the Reapers? Why has Cerberus come out of the shadows? Why is mankind the only species in the universe being hunted?