A giant metal planet lands on the new Namek planet, and begins eating it.
The Namek elders call to Dende for help, and Dende relays the call. This is
why Gokou, Gohan, Krillin, Kamesennin, Oolong, Yajarobe, and Piccolo get
into a spaceship and fly off.  (Vegeta is in his own space capsule, and he
arrives to ensure that Gokou lives long enough for him to kill Gokou
himself.)
   Turns out that Cooler has pulled a V'ger trick, and has become part of
the ship that is eating the Namek planet. Cooler's robot are sent out to
round up all of the Namek. Gokou's ship arrives in time for the Z
Fighters to also be picked up to be used to power the ship.  Gokou and
Vegeta fight Cooler, and get trashed. They are wired into the ship to
provide power for Big Geta Star. Gokou and Vegeta push the limits of their
Super Saiyan power, and cause Big Geta Star to overheat. Finally, Gokou
blows the real Cooler away, and Big Geta Star explodes.  (First time that
Vegeta shows up in the movies.)

                                       Characters
Cooler-- Old Cooler merged with some space junk to become the
               core of a giant spaceship.  Destroyed by Gokou.
Big Geta Star -- The name of the planet-eating spaceship.
Metal Cooler  -- Cooler-shaped robots, with self-repairing bodies.
                           All were destroyed when Big Geta Star exploded.
Muuri  -- One of the Namek elders. Lost and forgotten.
 
 
Dragonball Z Movies Sunny's Dragonball Village