Dr. Raichi is the main antagonist of the OVA Dragon Ball Z: Plan to Eradicate the Saiyans. He first appeared in the video game Dragon Ball Z Gaiden: Saiyajin Zetsumetsu Keikaku.
In the Tsufurians' prime, Dr. Raichi was the greatest scientist of their civilization. In Age 730, the Saiyans eventually massacred the entire Tsufurian race and conquered the planet, renaming it Planet Vegeta in honor of their king. Raichi makes a desperate attempt to escape with his most esteemed invention, Hatchiyack, but he is kicked towards his super computer and killed as his capsule prepares for liftoff. The capsule finds refuge on Planet Dark, a planet at the end of the universe. There, the super computer Hatchiyack continues incubating until it conceives the ghost squadron; among them is a renewed Dr. Raichi, Ghost Raichi (ゴースト・ライチー), whose only wish is to eradicate the last remaining Saiyans.
Ghost Raichi calls himself the ultimate ghost warrior created by Hatchiyack, though it is unknown what it means in terms of fighting ability. In the OVA, his energy shield is able to hold up against the combined efforts of Son Goku, Vegeta, Son Gohan, Future Trunks, and Piccolo for a short while until it eventually gives way to their power. Raichi is then easily dispatched by Vegeta's Final Flash.
The scientist releases Destron Gas on Earth, which disturbs the Z Fighters concentration in using ki attacks. They defeat the monsters that guard the Destron generators, then Ghost Warriors of past villains appear to attack. This is all part of his plan to lure Goku, Gohan, Future Trunks and Vegeta (the last remaining Saiyans) to the Dark Planet. Once on there, they battle Dr. Raichi, whose only attack is a barrier. Once the barrier is shattered, Vegeta blasts Raichi with a Final Flash attack. After Raichi rematerializes and tries to form a shield once again, Vegeta brutally executes him, shattering the barrier along with him. When a small fragment of Raichi falls to the ground and screams with all his hatred of the Saiyans, Vegeta crushes what remained of him under his foot.
- In Plan to Eradicate the Super Saiyans, the remake of The Plan to Eradicate the Saiyans, Dr. Raichi has a more bluish tone and a beard instead of a long mustache.
- The concept of, and even some aspects of Dr. Raichi's appearance, were recycled into the Machine Mutant that is Dr. Mu in Dragon Ball GT.