Since Dragon Ball GT is a long continuation of the long series known as Dragon Ball. The series is about a young boy Goku who is now grown and he has been through a lot of adventures in Dragon Ball and Dragon Ball GT.
Goku is now turned into a young by the Ultimate Shenron. Now Goku along with Pan and Trunks embarked upon adventures and ultimately faces a notorious creature an artificial Tuffle Parasite.
Tuffle parasite, despite being a parasitic creature has a unique ability that it gets into the body of its host and tries to combine his powers with the power of its host and become an ultimate powerful being
Truffle intends to destroy the Saiyan species, for which he fights with Goku by fusing into the body of many hosts, and ultimately he gets into the body of Vegeta and tries to kill Goku.
Goku manages to beat Tuffle by achieving the stage of Super Saiyan 4 and regenerates its tail. Piccolo sacrifices his life to restore the Black Star Dragon Balls’ loss of lives of the people.
But Dr. Myuu and Dr. Gero revive Android 17 in hell who tries to control the original Android 17 to open the hell portal to Earth but Krillin intervenes and as a result of his intervention Android 17 kills Krillin.
But Goku fights back and avenges the death of Krillin. Afterward, they collect Dragon balls to summon the Dragon to restore the loss of precious lives but after collecting all the balls advents the Shadow Dragons who decide to punish people of the earth due to their misuse of Dragon Balls.
Among many Shenron, Syn Shenron becomes Omega Shenron whom Goku cannot defeat all alone and it marks the event where Goku and Vegeta fuse to transform into Gogeta but still their new transformation and powers they can’t compete against Shenron.
After splitting up, Goku derives energy from all the creatures of the earth to form a Universal Spirit Bomb and manages to defeat Syn Shenron.
Later in the story, they summons the Dragon by collecting all the balls to bring back everyone to life that lost his life to the attack of Android 17 and Shadow Dragons.
Now many years have passed and Guko Jr who is the great-great-grandson of Goku and Vegeta Jr who is competing against each other in a tournament where Goku after wrapping up every event and having flashbacks of the old timeline leave the crowd and it marks the end of the story.
Since Dragon Ball is one of the greatest anime series one can watch; one should go through Dragon Ball GT Filler List as well to unfold many great events and fights of Dragon Ball GT.