The danger for superhero collections for any serialized storytelling, really is the risk of alienating new readers with complex backstories and plotlines. This volume, serving as both an origin tale for longtime archenemy Professor Zoom and as a precursor to DC's line-shattering Flashpoint event, runs that risk more than most. If you're entering in the middle and leaving in the middle, why should you engage and invest? Johns counters this concern with a story that, though heavily entangled in continuity, compellingly focuses on the emotional journey of the Flash as he tries to reconcile with his past and his family while investigating a case of murder by premature aging and the arrival of a doppelganger from a parallel time line. Meanwhile, Kolins' always-solid art basks in standout color work that paints the action in crackling reds and yellows and the human end of the story in soft greens, browns, and beiges for an extra layer of emotional texture. A fine, fun example of sci-fi superheroing.--Karp, Jesse Copyright 2010 Booklist