The planet is being invaded by parasitic shape-changing aliens who have a taste for spinal fluid. While many of their victims die, the survivors find themselves with superpowers. These new heroes (among them Tommy Monaghan) must band together with the old to repell the alien invasion.
This is the 2nd Chapter of the Bloodlines cross over. It continues from OutBreak and continues in DeathStorm. The reading order for this arc is as follows: Part 1) Robin Annual #2, Part 2) Action Comis Annual #5, Part 3) Legion of Supre-Heroes Annual #4, Part 4) Green Arrow Annual #6, Part 5) Detective Comics Annual #6, Part 6) Justice League America Annual #7, Part 7) Adventures of Superman Annual #5, Part 8) Hawkman Annual #1.