Over the years a number of different characters have assumed the title of Ant-Man, most of whom have been connected with the Avengers.
The original Ant-Man was Biophysicist and Security Operations Center expert Dr. Henry 'Hank' Pym; who decided to become a superhero after the death of his first wife Maria Trovaya, who had been a political dissident in Hungary. Falling in love with him and believing that his American citizenship would protect her, Hank and Maria traveled to Hungary shortly after their marriage to start their new life together. Unfortunately they were confronted by corrupt agents of the secret police. Hank 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. After discovering a chemical substance, which he called Pym Particles, that would allow the user to alter his size, he armed himself with a helmet that could control ants. After that, Pym would shrink down to the size of an insect to become the mystery-solving Ant-Man, solving crimes and stopping criminals. He soon shared his discovery with his new girlfriend Janet van Dyne, who became his crime-fighting partner The Wasp, when he helped her avenge the death of her scientist father Vernon van Dyne who was killed by an alien unleashed by one of Vernon's own experiments. The duo would become founding members of the Avengers, fighting recurring enemies such as the mad scientist Egghead, the mutant Whirlwind, and Pym's own robotic creation Ultron. While Pym is the original Ant-Man, he has adopted other aliases over the years including Giant-Man, Goliath, Yellowjacket, and Wasp after Janet's presumed death in Secret Invasion. Leaving his original persona vacant, his successors have taken up the Ant-Man role while Pym explored these other identities.
Scott Lang was a thief who became Ant-Man after stealing the Ant-Man suit to save his daughter Cassandra "Cassie" Lang from a heart condition. Reforming from his life of crime, Lang soon took on a full-time career as Ant-Man with the encouragement of Hank Pym. He became an affiliate of the Fantastic Four, and later became a full-time member of the Avengers. For a period of time he dated Jessica Jones. He was killed by the Scarlet Witch along with the Vision and Hawkeye in Avengers Disassembled, and his daughter took up his heroic mantle as Stature in the book Young Avengers. He returned to life in 2011 in the mini series, The Children's Crusade, but lost his daughter when she heroically sacrificed herself to stop a super charged Doctor Doom, who would later revive her during the AXIS.
Eric O'Grady is the third character to take up the Ant-Man title. O'Grady is a low-level agent of S.H.I.E.L.D. who stumbles upon the Ant-Man suit in S.H.I.E.L.D.'s headquarters. A man of few morals and willing to lie, cheat, steal and manipulate in order to get ahead in life, Eric stole the armor for his own selfish plans, which included using his status as a "super-hero" to seduce women and humiliate and torment others. He had his own short-lived title before being part of other teams such as joining Avengers: The Initiative as his first team and then joining The Thunderbolts but more recently Secret Avengers, where the character perished heroically while defending a child against the villain known as Father.
A live-action film, featuring Scott Lang and Hank Pym, titled Ant-Man, was released on July 17, 2015. The film is directed by Peyton Reed, with a screenplay by Edgar Wright & Joe Cornish and Adam McKay & Paul Rudd from a story by Wright and Cornish. Wright was slated to direct the film but left the project in May 2014 due to creative differences with the studio. In November 2013, Kevin Feige confirmed that aspects of Eric O'Grady's Ant-Man would not be featured in the film. In December 2013, Paul Rudd was cast as Ant-Man, followed in January 2014 with the casting of Michael Douglas as Pym, and the confirmation of Rudd as Lang. Reed said the costume design was influenced by Asian tokusatsu superheroes such as Ultraman and Inframan.