All Monsters Attack (aka Godzilla's Revenge) - Region 1 DVD

Ichiro is a latch-key kid in the late 1960s Japan, a country drowning in urban blight and big, nasty bullies. He escapes his dreary life by dreaming of Monster Island, a fantasy world where Godzilla rules and Ichiro is befriended by Godzill'a son, Minilla, who's experiencing his own troubles with a bull monster, Gabara. When Ichiro is kidnapped by crooks, the lessons learned from his monster pals help him stand up for himself and fight back.