After Goku dies, he goes to the other dimension where he runs along snake way for about a year before reaching King Kai. While running on snake way, he runs into a street cleaner and asks for a ride. During the ride, he falls asleep and falls down below the orange clouds into a place called HIFL(Home for infinite losers). In the japanese version, it's called Hell. While there he races a red guy and fights a blue guy beating both. They tell him the way to get out and back onto snake way. Except that Goku's back at King Yama, so he starts running again.W hile training with King Kai, a monkey named Bubbles and a cricket named Gregory, Goku learns the Kaio-Ken attack and the Genki Dama (Spirit bomb). Meanwhile, Yamcha, Krillen, Chouzu, Tienshinhan and Yajirobe are training on Kami's lookout for the arrival of the saiyans Vegeta and Nappa. Yajirobe doesn't train very much but eats most of the time. (Even though he doesn't always show it, Yajirobe isn't all that bad of a fighter, but is no caparison to the Z Fighters). Goku, Yamcha, Tien, Chouzu, Krillen and Yajirobe aren't the only ones training either. Piccolo took Gohan to train for the arrival of the Saiyans.
Finally, the Saiyans Vegeta and Nappa arrive on Earth. Their scouters detect that there are over a dozen people with power levels of over 1000. They seek out the most powerful ones which are Gohan and Piccolo. They arrive and plant siz little green Saibamen whom each has a power levels of that of Radditz. Their fate isn't looking good, but then the rest of the Z fighters arrive. Yamcha gets blown up by a self-destructing Saibamen. Krillen kills the rest. Chouzu attempts a self-destruct on Nappa killing himself but barely leaving a scratch on Nappa. Tien tries one last blast and then dies using up his energy. Nappa then shoots one huge blast at Gohan, but Piccolo steps in the way killing him.
Finally, Goku arrives. He really beats up Nappa and then to their surprise, Vegeta kills Nappa because of Nappa's ignorence. Goku the battles Vegeta. Eventually Vegeta shoots his Galick Gun Hoping to destroy Earth but Goku counters with a mighty kame-ha-me-ha and blasts Vegeta into the sky. But Vegeta's not done yet. He creates a fake moon in the sky and turns into an oozaru. He then beats up Goku after Goku made a failed attempt to shoot a spirit bomb at him. Gohan comes but also gets beaten up. Meanwhile, Yajirobe is watching the whole thing and finally slices of Vegeta's tail returning him to normal size. Krillen the takes the spirit bomb energy goku gathered earlier and shoots it at Vegeta making a direct hit. Vegeta's not done yet though. He injures Krillen, but not as much as Gohan and Goku. Since Vegeta is seriously wounded from the spirit bomb, he tries to escape in his space pod. Krillen is about to kill him when he gets a telepathic message from Goku telling him not to kill Vegeta. Vegeta leaves vowing revenge against Kakkarot(Goku's Saiyan name).