In this story, the Goblins, usually friendly with the Fireflies, exclude them from a moonlit party because their light isn't needed, making the Fireflies feel used and unappreciated. Led by an elder, the slighted Fireflies devise a clever revenge: while the Goblins are away sailing, thousands of Fireflies cover their rock homes and glow steadily, tricking the returning Goblins into believing their homes are on fire. Panicked and sleepless, the Goblins hide until morning, only to find their homes unharmed, eventually suspecting the Fireflies' trick. This experience teaches the thoughtless Goblins a valuable lesson about true friendship and consideration, ensuring they always invite the Fireflies to future gatherings, regardless of needing their light.