This movie opens with Bulma, Krillin, Gohan, and Oolong camping in the woods. Sometime during the night a ufo crashes in the forest causing a huge forest fire. Krillin and Gohan manage to put the fire out, but the forest has been burned to the ground. During this time Gohan rescues Hiya-Dragon, who accompanies Gohan for the next two movies and a few episodes. They decide to use the Dragon Balls to restore it. (In the Japanese version it shows everyone searching for the Dragonballs during the Cha La Head Cha La theme, but that was left out in the regular English version for some reason.) Anyway they summon the Dragon, and restore the forest.
The ufo comes out of the ground and reports data for Earth back to the "mother ship", which is led by a Saiya-jin named Taurus (Turles), who looks exactly like Goku except darker.The next few scenes deal Gohan, Hiya-Dragon, Chi Chi and Goku and whether or not Gohan can keep Hiya-Dragon. Goku helps Gohan hide Hiya-Dragon in cave despite Chi Chi not wanting Gohan to keep it.
A few minions of Taurus blow a hole in the ground and plant seeds for the World Tree Of Might. The explosion wrecks Yamcha's new cruiser. Everyone is at Goku's house and King Kai telepathically warns Goku about the World Tree Of Might. Goku, Yamcha, Tenshinhan, Chaoutsu, Krillin, and Gohan go to destroy the World Tree Of Might. When they get there, they are forced to battle the minions who planted the Tree of Might. Gohan fights two twin minions and Taurus notices Gohan's power reading from the ship and realizes Gohan is Goku's son.
Taurus goes and tries to persuade Gohan to join him in taking over the universe, but Gohan refuses. Taurus then pummles Gohan until Piccolo shows up. Taurus overpowers Piccolo and creates artifical moonlight and holds Gohan's face to it. Gohan transforms into Oozaruu form, and Taurus destroys the light so he isn't affected as well. Taurus' minions attack Goku, but they are killed. Goku tries to reason with Gohan, but Gohan can't be reasoned with when in Oozaruu form. Hiya-Dragon shows up and Gohan calms down. Taurus is enraged that Gohan has a soft spot for Hiya-Dragon and creates a huge ki blast to kill Gohan. Goku cuts off Gohan's tail, and Gohan detransforms before the blast hits. Now Goku faces Taurus.
Goku and Taurus fight, but Taurus grabs a piece of fruit from the World Tree Of Might and eats it. Taurus' power increases and he pummels Goku. Goku tries a Genki Dama, but the World Tree Of Might has already drained to much energy for it to do any good. Taurus easily overpowers the Genki Dama with one of his own ki attacks. It now seems that Taurus has won, but Goku draws energy from the World Tree Of Might. Goku gets the strength to move around and confronts Taurus one last time. Taurus is shocked to see Goku. Goku explains that the World Tree Of Might can also give energy and Goku throws another Genki Dama at Taurus. Taurus' scouter breaks and he tries to stop the Genki Dama with a ki attack, but it doesn't work. Goku's Genki Dama attack kills Taurus and destroys the World Tree of Might. The energy falls back down to Earth in a golden snow.
Rating: 7.5/10, Because this was the first Dragon Ball Z movie I saw, and I consider it to be one of the better movies.