Alex Summers was a mutant who was placed in prison for killing the man who had abducted him and his sister. In 1962 his release was arranged by Charles Xavier and Erik Lensherr in order for him to join the team of mutant peacekeepers they were forming for the CIA. The warden cautioned them about putting him with others in a group, as Alex was the only prisoner he'd known to actually prefer solitary confinement.
While bonding with Xavier's other recruits, the secret CIA facility where they were staying was attacked by the Hellfire Club. Their leader, Sebastian Shaw, encouraged them to join him in overthrowing humanity. Angel Salvatore accepted the offer, and when Alex attempted to hit Shaw with his energy waves, Shaw absorbed the blast and used the energy to murder the mutant Darwin.
Controlling His Powers
Afterwards, Alex and the others relocated to Xavier's mansion where they began training to defeat Shaw. Team member Hank McCoy constructed a containment unit for him, allowing Alex to focus his energy blasts. After a successful test he had one built into his X-Men uniform.
During the Cuban Missile Crisis, when the team assembled to finally confront the Hellfire Club, Summers was impressed with Hank McCoy's ferocity accompanying his beastial transformation and dubbed him "Beast". He and Hank fought the mutant Azazel and he also faced Angel Salvatore alongside Banshee.
In 1973, Havok was no longer a member of the X-Men, but a soldier stationed in Saigon during the Vietnam War. Before he was to be sent home, Major Bill Stryker rounded up Summers and three other mutant GIs to be sent to Trask Industries to be studied, but a last-minute intervention from Mystique prevented this and allowed all four soldiers to return home safely. Alex had a brief talk with Mystique before leaving.
In 1983, Havok's younger brother Scott began developing his mutant powers as well. Scott struggled controlling his optic laser blasts just as Alex struggled controlling his plasma generation decades prior. He convinced his parents to bring Scott to Xavier's School for Gifted Youngsters. He brought Scott there, and reunited with Hank McCoy, who wasn't "blue and furry" anymore, and Professor Xavier. He had Scott demonstrate his powers in the backyard. Scott ended up destroying Xavier's favorite tree, but Xavier enrolled him anyway.
Alex accompanied Xavier to see Agent Moira MacTaggert. It was awkward for Xavier, as he had erased her memories of him and the X-Men, and she had moved on with her life while Xavier still harbored feelings for her, and Alex teased him for it. They went to the CIA Headquarters and gathered information from Moira about a sudden pulse that rocked the entire globe, which originated in Cairo, Egypt. Moira filled them in about how many mutant-worshipping cults had formed since the revelation of mutant existence in 1973, and about how some of these cults had tracked down the body of En Sabah Nur, someone they believed to be the world's first mutant. She also informed them of how he would gather four powerful followers, his Horsemen. Xavier asked Moira to accompany him and Alex back to his campus in order to get more information.
When they arrived, they found Mystique there, waiting for Xavier. Xavier asked to be excused for a moment, so Alex and Moira waited. They, joined by Hank, then went to Cerebro to locate former teammate Magneto. However, En Sabah Nur had apparently inducted him into his Horsemen, thus giving him the opportunity to tap into Cerebro and use it himself. Xavier lost control of Cerebro, and told Alex to wreak havoc on Cerebro. Alex fired his plasma at Cerebro, destroying it. When they exited Cerebro, they were met by En Sabah Nur and his Horsemen, who had just teleported in. They kidnapped Xavier and began to teleport away. Alex ran and shot a laser blast at them, but they disappeared before it could reach them. The laser blast ended up shooting through the door behind them, hitting Hank's new X-Jet. Alex, being the closest to the X-Jet, was caught in the immediate explosion, while the others and the students of the school were saved by the timely intervention of mutant speedster Peter Maximoff.
Plasma Generation: Alex is capable of generating rings of highly destructive energy and dispersing it. While using his powers by himself he must manifest it as a ring by spinning his entire body and typically had a hard time directing the rings. Hank McCoy made him a suit that allowed him to channel his power into a beam and making it much more effective. The energy seemed to burn through solid objects with ease. When released as rings, they are able to cut right through a metal statue.
- In 2011, Director Bryan Singer said that it "wouldn’t physically fit for [Alex] to be the brother of Cyclops". It's ironic, given the fact that he directed the film that ended up introducing Cyclops as Alex' brother.