Watch Dragon Ball Z: The Tree of Might

Dragon Ball Z: The Tree of Might is an OVA movie from the Dragon Ball Z anime. As it takes place within an established series, the continuity of the film lies somewhere between the defense of Earth against Saiyans, Vegeta and Nappa, and the Z-Fighters' leaving Earth to recover the Namekian dragon balls. The film begins with a massive forest fire, with the Z-Fighters herding any straggling animals out of the battle zone. Among these animals is a young dragon, named Icarus, who instead becomes a pet to Goku's son Gohan. Sometime later, a group of Saiyans appear and toss a special seed into the ground. This seed quickly grows into the titular Tree of Might, a parasitic plant which draws upon a planet's life force to grow its fruit. The Fruit of Might gives the consumer an immense rush of power and speed.

As the Z-Fighters go to deal with the Saiyan force, they learn that the group's leader, Turles, bears a striking similarity to Goku, albeit with a more tanned complexion. Turles gives Goku a choice between joining his own kind or death. Goku easily turns down the offer and battles Turles. The Namekian Piccolo joins in the match just in time to save Goku's life, which infuriates Turles enough to create an artificial moon. With the moon in sight, Gohan turns into the Giant Ape form of his race and nearly ends the Z-Fighter's lives. However, Goku cuts off his son's tail, reverting Gohan back to normal. Turles realizes enough time has passed for the fruit to be potent enough and so he consumes one, easily beating down Goku from a sheer excess of power and speed.

The Z-Fighters swarm Turles, distracting him long enough to allow Goku to get to his feet and summon a massive Spirit Bomb, which he hurls at Turles and the Tree of Might, ridding Earth of both threats in one shot.