Thousands of years ago, a being known as Nightmare appeared and created a company called NightMare Enterprises, often abbreviated as N.M.E. (Holy Nightmare in the Japanese version). It was in truth a front for his great armies of monsters, which he used to take over much of the universe. They devastated countless planets. But there were those who stood to combat his evil, in the form of the Star Warriors and the Galaxy Soldier Army. They fought for many thousands of years, but Nightmare's demon beasts outnumbered them, and killed most. However, everyone is quite surprised when Kirby's ship crashes close to Cappy Town (Pupupu Village in the Japanese dub) on the planet Pop Star. They find he is tiny, round, pink, and a child, unlike Tiff's desire of a strong knight. Despite his hardly warrior-like characteristics, he is quick to save anyone who is in danger. He is soon befriended by the siblings Tiff and Tuff, along with their servants Fololo and Falala.

The ruler of Dream Land, King Dedede, is jealous and suspicious of Kirby from the start. He and his sidekick Escargoon constantly try to get rid of Kirby with demon beasts provided by the company for a high fee, though Escargoon shows a great deal more reservation and morals.^{[original research?]} However, these attempts usually fail because of Kirby's natural abilities. Just as in the games, Kirby can inhale enemies and temporarily gain their powers, transforming into forms such as Fire Kirby with the ability to spit flames, or Sword Kirby to literally slice foes into pieces.

Kirby grows and becomes stronger before his final battle with Nightmare. In the end when Kirby and Tiff face Nightmare, which is in a dream, Tiff throws the Warp Star at Kirby, who swallows it and becomes Star Rod Kirby. Star Rod Kirby has the Star Rod which is Nightmare's sole weakness, allowing Kirby to defeat him.