The Iron Man is the titular protagonist of Ted Hughes' children novel of the same name, and the basis for The Iron Giant. Like the Giant, the Iron Man is a metal-eating robot of unknown origin, but he does not appear to have built as a weapon. Indeed, it was never stated where the Iron Man came from.
While gazing out at the sea, the Iron Man fell from the top of a cliff, breaking apart as he fell, but manually reassembling himself later. Unfortunately, he couldn't find one of his ears, abandoned the hunt and wandered out to sea. Some time later, he returned to land and began eating local machinery, but was spotted by young Hogarth Hughes, whose father tried rallying all the locals together in response to Hogarth's story. They prepared a trap in the form of a large pit, which the Iron Man would fall into while trying to get at a rusty old tractor. He didn't return as quickly as they would have hoped, and the tractor was removed. When the Iron Man did return, Hogarth lured him into the pit, tapping a rusty nail and a knife together, hoping the sound would attract him. With the Iron Man trapped, he was swiftly buried, and would not be seen again until the following spring, when he burst out of the hill the farmers had made.
Hogarth appealed to the Iron Man and persuaded him to follow the farmers to the local scrap yard, where the Iron Man could feast on scrap metal to his heart's content. The Iron Man would later be called into action when a gargantuan malevolent star spirit, described as a space-bat-angel-dragon, landed on Australia and demanded to be fed, lest it devour everything on the earth's surface. The Iron Man, thinking quickly, challenged the dragon to a contest of strength and willpower. After lying on a bed of girders above a raging fire til he was white-hot, he ordered the dragon to lie on the sun until it was equally hot. This ordeal continued twice over for both the dragon and the Iron Man, until the scorched weeping dragon surrendered, while the Iron Man escaped with a slightly melted ear. According to the Iron Man's rules, the dragon was now his slave, and his first order was for the dragon to orbit the earth every night, singing the music of space, which eventually led to world peace, while the Iron Man returned to his leisurely life in the scrap yard.
He would later be called into action when Hogarth had encountered young Lucy and The Iron Woman, who sought vengeance against a local waste management facility, which was poisoning the local marsh and river. Sympathetic to the Iron Woman's goals, but not wishing to destroy those who worked in the facility, the Iron Man told her the only option was for the people to experience a massive change. With that, he summoned the space-bat-angel-dragon from the moon, which compressed all its power into the Iron Woman, allowing anything that she wished to become possible. At her whim, men all over the country transformed into giant versions of water-based animals, until a creature known as Mess, the spider-god of wealth and greed appeared, and the Iron Woman and Iron Man battled it from its insides, until its cloudy body was dragged into space by the space-bat-angel-dragon.