Doctor Henry "Hank" Pym is an entomologist and physicist who developed the Ant-Man suit after discovering the Pym Particles. He also briefly made the design schematics for the Ultron Sentry unit alongside Howard Stark during his tenure at SHIELD, but the idea was later scrapped due to creative differences between the two inventors. Eventually, tragedy struck when Hank's wife Janet was lost during a mission to stop the Ten Rings from launching a missile at the United States. Hank then left SHIELD in depression and began his own company, Pym Technologies, which would later be renamed Cross Technological Enterprises upon his retirement and the ascendance of his former assistant, Darren Cross, to the rank of CEO. The death of Janet and Hank's ever-growing need to find her in the meantime caused a estranged relationship between Hank and his daughter Hope.
When Darren, corrupted by an infusion of Hank's unstable mind into his own subconsciousness, attempted to sell both the Pym Particles and a suit similar to that of Ant Man to Mitchell Carson's HYDRA squadron, Hank realized he would the help of a expert thief in order to steal the Yellowjacket suit back from him.
Hank then allowed expert thief Scott Lang to steal his suit, and later helped Scott out of jail when he was arrested for returning the suit. When Scott was brought to Hank's house, Hank and Hope trained Scott in becoming the second Ant Man.
Hank then assisted in the defeat of Darren, and after the conflict, Hank showed his daughter the Wasp Mark II and now helps her in finishing it.