Dr. Henry "Hank" Pym, is an American biochemist with extensive knowledge in various scientific fields, married Maria Trovaya, a brave and beautiful young woman who had been a political dissident in her native Hungary, from which she had fled. Naively believing that his American citizenship would protect her, Henry and Maria Pym traveled to Hungary shortly after their marriage. The Pyms were confronted by agents of the secret police there. Henry Pym was knocked unconscious and Maria was murdered. Pym was greatly distraught by his wife's death, and decided to do whatever he could in the future to battle injustice and inhumanity.
Back in the United States, Pym discovered a rare group of subatomic particles, which have become known as the "Pym Particles." Pym was able, through the application of magnetic fields, to entrap the particles within two separate serums. One serum would reduce the size of persons and objects, and the other would restore them to their normal size. Pym tested the reducing serum on himself and discovered it was more powerful than he had expected: it reduced him to the size of an insect. Pym became entrapped in an anthill and was pursued by the ants within. He escaped and restored himself to his normal size with his other serum. Deciding that the serums were too dangerous to exist, Pym destroyed both of them.
However, weeks later he reconsidered his decision and began to recreate the serums, whose existence he then kept secret. Inspired by his experience in the anthill, Pym undertook a study of ants, and theorized that ants communicate through psionic / electrical waves transmitted through their antennae. After months of work, Pym succeeded in creating his first "cybernetic helmet," which would enable him to communicate with ants through transmitting and receiving psionic / electrical waves. Thinking that someday he might want to use the shrinking potion on himself again, Pym also designed a protective costume for himself, Unstable Molecules and steel mesh. That same day, however, Pym received an assignment from the government to concoct a gas that would provide people with temporary, limited immunity to radioactivity under certain specific circumstances, based on his previous work. The government also assigned four other scientists to assist him in the project. The KGB, the Soviet Intelligence agency, learned of Pym's project and sent agents who held Pym and his assistants prisoner in their own laboratory. Only Pym knew the entire formula for the gas they had by now developed, and he refused to tell the Soviet agents. The agents set about searching the laboratory for the formula, intending to kill Pym and his assistants afterward. Unseen, Pym donned the cybernetic helmet and protective costume and, using his reducing formula, shrank himself to the size of an ant. He escaped to an anthill outside, put a large number of ants under his control through the helmet, and used them to attack the agents and free his men, who then overpowered their assailants. Pym then restored himself to normal size. Afterwards, in the guise of the Ant-Man, Pym battled various menaces, including Comrade X, the Protector, the criminal scientist Elihas "Egghead" Starr, who was to become Pym's greatest enemy, as well as the Scarlet Beetle, the Hijacker, the alien Kulla, the Voice and the Time Master.
After an alien being from the planet Kosmos killed Pym's colleague, the scientist Vernon van Dyne, Pym revealed his secret identity of Ant-Man to van Dyne's daughter Janet, who wished to avenge his death. Pym taught Janet how to use the gas within which he now contained the "Pym Particles," and which he used to shrink himself in size, and through biochemistry, gave her the ability grow insect-like wings when she used the gas to shrink herself to insect size. As the Wasp, Janet van Dyne assisted the Ant-Man in finding and defeating the murderous Kosmosian. Pym and van Dyne gradually fell in love; van Dyne reminded Pym of his deceased first wife, Maria. Pym and van Dyne became crime-fighting partners in their costumed identities, fighting menaces like the Egghead, the A-Chiltarians and their robot Cyclops, the trumpet-playing criminal Trago, the Porcupine, the Human Top and the Black Knight (Nathan Garrett). They were two of the founding members of The Avengers and were part of the group that discovered the frozen form of Captain America, bringing the World War II hero into the modern world.