During summer vacation, Nobita is accidentally stranded after drifting away in a tiny bamboo boat while shrunk by Doraemon’s “Gulliver Tunnel.” Doraemon and Shizuka try to rescue him, but Gian and Suneo insist on shrinking down too so they can experience the miniature world themselves. As the group travels through the dangerous micro-world to find Nobita, they are attacked by a crow while riding a balloon raft. In the chaos, Doraemon accidentally drops the “Big Light,” the gadget needed to restore their normal size, making the rescue even more difficult.