The JLA guest-stars in the senses-shattering conclusion to "Justice For All." For months, J'onn has been plagued by the ruthless machinations of Malefic. Now, pushed to the edge of his endurance, the Martian Manhunter and his allies from the JLA battle J'onn's brother in one of the most astonishing showdowns of the year!

Although Malefic is largely successful in pitting the Justice League of America against each other through his shape-shifting manipulations, his one true threat has returned in the form of J'onn J'onzz - the Martian Manhunter. As a result from absorbing mass from the Earth, J'onn is unable to control his shape-shifting and remains in his Manhunter form while battling his physically superior twin brother. The two battle aboard the flying city of Z'onn Z'orr, and only one will survive.