While traveling through an asteroid field, the Searcher discovers a stasis capsule with what appears to be a "gold boy" within (the alien's skin tone is the color of gold, as opposed to a boy made of gold – as confirmed by Dr. Goodfellow). Upon reviving from stasis, the alien declares his name is Velis and he desperately wishes to know where his companion, Relcos, is and that he must find him.
Soon thereafter, the Searcher is struck by an asteroid, and Asimov is trapped under a fallen piece of debris, too heavy to be moved by four crewmen, including William "Buck" Rogers and Hawk. Velis comes to Asimov's aid by touching the debris which then becomes easy to lift by psychokinetic chemistry (the ability to change the density/molecular structure of metals).
While attempting to get to the nearby planet Iris VII, whereon Relcos is believed to have landed, the Searcher is trapped on a large asteroid, unable to free itself using its tractor beams in reverse. Velis is unable to lighten the entire Searcher; however, he declares his companion, Relcos, is larger and whose powers are stronger would be able to do so. Buck, with a bit of trepidation, takes Velis to Iris VII to find his companion.
On Iris VII, Relcos has been captured by the local population and is placed in a cage wherein the townspeople force him to change their base metal utensils into precious metals. Relcos escapes by changing the metal bars to glass.
Buck and Velis are captured and jailed soon after arriving on Iris VII, it is at this point they are informed that Iris VII is a penal colony. Velis also reveals to the authorities that he, and Relcos, can transmute metals. The authorities then bring Velis to a rocketship and force him to attempt to change its weight, but he is unable. The authorities then decide to find Relcos, while jailing Buck and Velis.
Freeing themselves, Buck and Velis meet up with Hawk, who has been informed by Dr. Goodfellow that Iris VII is a penal colony and has come to the planet posing as a Federal Official. The trio is reunited with Relcos, who has been befriended and kept safe by a local stable boy, Marcos; but is later recaptured by the authorities of the penal colony. Hawk is exposed, but he, Buck, Velis and Relcos flee and manage to escape.
Later, aboard the Searcher, Relcos lightens the starship and it is able to use its tractor beams to free itself from the asteroid; repaired the ship is able to continue its travels. Velis reveals to Buck that Relcos is not the adult he appears, nor is Velis the child he appears; in fact Velis is Relcos's father. Their species age in reverse to humans with Relcos being only 5 years old.
