Bardock, the father of Raditz and Goku, was a low-class Saiyan who worked for Frieza, roaming the galaxy, conquering planets. While destroying a planet he is cursed with the ability to see the future by an alien. While Bardock is recovering from a wound, his team sets out to conquer a planet, believing they will be fine without Bardock's help. They are defeated, however, by a group of Frieza's elite warriors.
Frieza saw that Bardock and his squad was growing in power greatly from the battles they fought, and sought to end their progression. Bardock arrives at the scene of his squad's death, and confronts Frieza's elite team. At first, it appears as if the squad has the upper hand, but Bardock soon displays his true power, demolishing his enemies. This surprised the elite team because they thought Bardock to be weak because of his low ranking.
He is struck down after, however, by Dadoria, Frieza's henchman. Bardock returns to planet Vegeta, barely alive, and attempts to recruit the other Saiyans to stand against Frieza. Gaining no support (most are afraid of Frieza's wraith), Bardock sets out to confront Frieza by himself.Bardock barrels through Frieza's men surrounding his space craft, and stops with the planet Vegeta behind him. As Frieza emerges from his ship, Bardock launches his final spirit cannon, hoping to destroy Frieza.
Frieza retaliates with his own ball of energy, an attack large enough to destroy not only Bardock, but all of planet Vegeta. Before Bardock is obliterated, he has a vision that his son will be the one to avenge the Saiyan race by defeating Frieza. As he dies from Frieza's energy blast he has a vision of his son, Kakarot, transforming into a super saiyan and killing Frieza. This is helps him die peacefully knowing Frieza will eventually be stopped and by his own son.
The Episode of Bardock
After Frieza's attack, Bardock mysteriously awakens on another planet. Sure he had been killed, he soon realizes he is on Planet Plant, which was the original name of Planet Vegeta and assumes he has been sent back in time. When two members of the Planet Trade Organization arrives, he makes quick work of them.
While the Plants phrase him for his efforts, he flies off to be alone in a cave. He is befriended by a Plant named Berry, who brings him food.
But the disappearance of the Planet Trade Organization members did not go unnoticed. It attracts Lord Chilled, a distant ancestor of Frieza. While Bardock is able to easily defeat his minions, he proves no match for Chilled.
When Chilled attacks Berry, Bardock becomes angry with his lack of power. This forces him to transform into a Super Saiyan. He is easily able to defeat Chilled, who leaves a message with his last words for his family: Beware the Super Saiyan. This is the event that causes Frieza to fear the Saiyans and their growing power.