Dragon Ball GT - Season 1 - Eps 42: A Dangerous Union
In the depths of Hell, an evil union between Dr. Gero and Dr. Myuu takes place. Soon after, Trunks is ambushed by Android 17 as a warning to Goku... Come to Hell or Earth will be attacked! As Goku travels to Hell to meet an uncertain fate, a fleet of ancient enemies flood the earth on a mad rampage!
About Dragon Ball GT

Title: Dragon Ball GT
First Air Date: 1996-02-07
Last Air Date: 1997-11-19
Status: Ended
Rating: 7.7/10 (from 1951 votes)
Language: JA
Seasons: 2
Total Episodes: 64
Network: Fuji TV
Genres: Animation, Action & Adventure, Sci-Fi & Fantasy
Production Companies: Bird Studios, Toei Animation, Toei Company, Fizz Sound Creation
Synopsis
Ten years have passed since Goku left his friends and family to hone his skills. But Goku soon finds himself helpless against the mystical power of the Dragon Balls and an accidental wish made by the devious Emperor Pilaf. The wish; that Goku once again become a child! Goku, together with Trunks, and his own granddaughter Pan, blast off into the outer reaches of space in search of the mysterious Black Star Dragon Balls. But these Dragon Balls have a fatal secret: if not collected within one year Earth will be destroyed.
Cast

Masako Nozawa
Son Gohan / Son Goku / Son Goten (voice)

Yuko Minaguchi
Pan / Videl (voice)

Takeshi Kusao
Trunks (voice)

Bin Shimada
Son Para / Sūgorō (voice)

Atsushi Kisaichi
Oob (voice)

Ryo Horikawa
Vegeta (voice)

Toshio Furukawa
Piccolo (voice)

Miki Ito
Android 18 (voice)

Hiromi Tsuru
Bulma / Bra (voice)

Daisuke Gori
Blake Smoke Dragon / Enma-Daiō / Gyūmaō / Mr. Satan / Umigame (voice)