Based on

Movies like Force Five : Grandizer (1981)

"Will the merciless Vegan Empire destroy the planet Earth? Only one man can protect his adopted homeland from the Vegan's ruthless cunning, none other than Orion Quest and his starship GRANDIZER. Quest guides his space robot GRANDIZER to Earth, where he is befriended by Professor Valconian, who hides his massive machine and helps Quest adopt a new identity as an earthling. Upon learning of the planned attack by the evil Vegans, Quest and his GRANDIZER ship come out of hiding to protect his new home from the vicious onslaughts" - Back of the VHS cover description. Compilation film by Jim Terry, based on Episodes 1-2,7,17,23,26-27, 32 and 37.