As the Rebels fight offImperial forces attackingtheir Yavin base, an Imperialbomber crashes into the ruinsat the ancient Massassi ruinsrousing the fearsome Night Beast.The Beast fights and easily defeatsChewbacca and shrugs off blasterfire from Luke and Han beforedisappearing without a trace. Chewie isrescued, and a search for the Beast isundertaken - to no avail. The Rebelsdiscover that the Beast was left as a guardianof the Massassi ruins by its original inhabitants.Luke finally uses the Force to ferret out theBeast in a maze of underground tunnels below theruins. After a tense battle with the Beast, Lukecommunicates to it a means of rejoining itsmasters, and it sets off to find them.