Justice League of America, Vol. 1

The Atom and one of his scientific colleagues discover a universal "Element X" that connects all other elements; without X, nothing on Earth will work. They also discover, though, that X is deteriorating at an alarming rate so The Atom gathers the heroes of the League. While discussing things on the satellite, various alerts are triggered as symptoms of X's deterioration are found. As the heroes return to Earth, none of them notice an alien craft orbiting the moon. After the League travel the Earth, saving people and cities from disaster, the aliens make their move, landing in England and demanding payment before handing over the cure for the degradation of Element X. Despite their suspicions, the League are asked to round up various animals and articles from across the Earth, as well as one particular man.