Summarizes X-Men 56, reprints 57 (the main story, not the B-story of Jean Grey's powers) and 58, and reprints the first nine pages of 59.
The Living Monolith turns Alex Summers into Havoc, potentially the most powerful mutant with uncontrollable destructive powers. Back home, Lorna Dane tries out her newly-discovered magnetic powers only to be captured by the return of the Sentinels. Meanwhile, the Living Monolith, in his human form as Professor Abdol, convinces the local constabulary to arrest the X-Men, which the X-Men forestall by attacking them. In the confusion, Alex slips away to ponder his new fate and identity, only also to be captured by Sentinels. Using Cerebro, the X-Men discover Lorna's capture, causing them to split up: Iceman and Beast return to the US to find Lorna (as Bobby is infatuated with her); Angel, Cyclops, and Marvel Girl look for Alex.
In the States, Bobby and Hank investigate Lorna's disappearance, fun afoul of American policemen (and attack them), and learn from the TV news anti-mutant hysteria is back in full-force, now lead by Judge Chalmers of the Federal Council on Mutant Activities and Larry Trask, son of the deceased creator of the Sentinels, Bolivar Trask. Shortly after hearing Larry Trask blame his father's death three years ago on mutants, Bobby and Hank are attacked by Sentinels. After a battle inter-splicing scenes from Trask's television interview, Bobby allows himself to be captured so Hank can get away and seek help. Hank contacts the rest of the team still looking for Alex, who abandon the search for Alex to return home. Impatient Warren flies under his own power, letting Scott and Jean take a jet home.
Larry Trask begins his systematic destruction of mutantkind by goading Bobby and giving Alex his first costume. Bobby and Alex have difficulty working together, now that they both have feelings for Lorna. The troubles with Trask enable the Living Monolith to regain his powers, only to be captured by Sentinels. Warren and Mesmero are also captured, and we learn the "Magneto" of recent issues was only a machine. Soon the partnership of Chalmers and Trask disintegrates, revealing Trask is himself a mutant, whom the Sentinels also prepare to destroy.
We learn the Sentinels have captured almost every mutant on the planet (presently extant in the X-Universe), just as Beast, Cyclops, and Marvel Girl finally locate Trask's headquarters. They are on their own.