Dragon Ball Kai ep 1 - Prologue to Battle! The Return of Son Goku

The Planet Vegeta, Age 737.

"Man, Kakarotto looks a lot like Bardock."

"Sure does. Doesn't really take after Gine at all, though, does he?"
"Who?"

(Holy shit, I made it.)

Meet Bardock. He's a Saiyan Warrior of the Planet Vegeta.

And he's got a pretty big beef with his boss, Freeza.

Namely that Freeza wants to destroy the Planet Vegeta and everyone on it.

Bardock, the only Saiyan who knows of his plan, makes a final, lonely stand to stop him.

It doesn't work out.
(Ah, Bardock, you crack me up.)

Because of his relative low Battle Power at birth, Bardock's youngest son, Kakarotto, was sent to the frontier planet of Earth. The idea being that, while he grew, his vicious Saiyan nature would allow him to gain strength quickly while wiping out the population of Earth, so that Freeza and his people could sell it. (Probably to some off-the-grid weirdo, tbh.) But due to a chance meeting, that is not what happened at all.

Instead, the infant Kakarotto is found by the wizened martial arts master, Son Gohan.

Who gives Kakarotto the new name, Son Goku.

In years time, Goku would meet Bulma,

and they would go on a quest for the seven magic Dragon Balls,

and meet the eternal wish granting dragon, Shen Long.

Then Goku would meet his lifelong friend Kuririn, and train under the best martial artists in the world, like the wise and lecherous Muten Roshi...

... and the ancient sage of Karin Tower, Karin-sama.

Goku would participate in the Tenka-ichi Budokai, putting himself up against the strongest fighters under the heavens.

And he would face the lord of the Demon Clan, Piccolo Daimao.

As well as his reincarnation, Piccolo Jr.

And both times, Son Goku would claim victory, and save the world.

He'd even find himself married to the Gyumao's daughter, Chichi.

It was truly the adventure of a lifetime... Which is why Dragon Ball Kai has decided not to cover it in more than a flashback, instead focusing on the second, slightly less interesting half of Goku's career.

(Do you even have to ask at this point?)

Instead, this is the story of what happens after a weird alien saves the Earth.

A visitor from the stars...

... arriving in a vessel not unlike that which Kakarotto arrived 23 years ago...

... out of which steps a black haired man with perfectly smooth, hairless legs...

... and more hair on his head than should be allowed...

... Kakarotto's older brother, Raditz!!

Meanwhile, during the five years of peace since Son Goku defeated Piccolo at the 23rd Tenka-ichi Budokai, Goku and his young wife Chichi have passed their days in the land of Paozu where Goku grew up with Son Gohan. During which, Goku gave Chichi lots and lots of big, thick wood.

(Get your mind out of the gutter.)

Together they had a son, the four year old Son Gohan (Junior).

Who loves nature so much that it nearly gets him killed.

Oops.
(I wonder how often Darwin took a tumble off a waterfall before becoming a Naturalist?)

Yet to Goku, Gohan seems to have an uncanny way of always getting himself out of trouble. Like the time they fought Garlic Jr. and Gohan tossed him into the Dead Zone.

Elsewhere, the inheritor of the Demon Clan, Piccolo 2: Mazoku Boogaloo, stands about in a rocky wasteland because... well, it isn't like he can go into town and hang out at the pub. Trying (and failing) to take over the world three times will kinda do shit to your reputation.

But suddenly, Raditz appears.

"Unreal. How does he have so much hair on his head and none on his legs?!"

"It's called Nair™, bitch."

Piccolo doesn't like the cut of Raditz's jib,

so he hits him with a Bukurikimaha.

Which doesn't do much more than kick up some dirt around the Saiyan.

"Ah, poop."

But before Raditz can finish playing with Piccolo, the strange Scouter device on his face alerts him to a Battle Power even stronger than Piccolo's - this time, it has to be Kakarotto!

Meanwhile, Goku and Gohan take the Kinto'un out to Kame House to have a reunion with all of Goku's old friends.

There's Bulma, the hot one. Kuririn, the short one. Muten Roshi, the old one, and Umigame, the turtle.

Gohan likes Umigame best.

Their other friends aren't there because Bulma is mad at Yamcha, Puar only goes where Yamcha is, Tenshinhan and Chaozu are off somewhere faraway to train, and Lunch left five years ago to find them. And Oolong? Well... they forgot about Oolong.

(Do you even have to ask at this point?)

But far from that, everyone is more shocked that Goku brought a kid with him - and that it's his.

"So um, Son-kun... does that mean you, um... know where to... 'put it'."
"Put what?"

They chat for a bit about how Goku reckons Gohan is real strong, but Chichi has him focused on his studies and won't let Goku train him. Consequently, Gohan doesn't seem to mind. He rather likes the idea of becoming a great scholar one day. (But lord knows, don't tell the fanboys that.)

Then, Raditz shows up.

"Sup?"

And he brings word that he's Goku's older brother --

-- and that Goku's real name is Kakarotto!

"Kakawhat? Go home, buddy. You're drunk."

"Believe me now?"

"... guys. He's not drunk."