Doraemon: Nobita's Little Star Wars

One day, Nobita rescues a dog that nearly drowned and adopts him, naming him Ichi. To hide the dog from his mother, Nobita, Doraemon, and Shizuka use the Anywhere Door to escape to the back mountain, where they discover many abandoned cats and dogs. Together with Gian and Suneo, they bring numerous stray animals back in time to Earth three hundred million years ago—a time before any life existed—to establish a kingdom of cats and dogs. Nobita uses the "Evolution-Degeneration Ray Gun" to evolve Ichi into a human-like creature capable of understanding human speech. That evening, as Nobita prepares to return to the 21st century, he promises Ichi that he will come back tomorrow. However, while boarding the time machine, he accidentally drops his wooden ball there, which Ichi picks up. The next day, on their way back to three hundred million years ago, Nobita and the others encounter a time warp and are transported to one thousand years after that era. They find themselves in an international city inhabited by cats and dogs. Nobita realizes that because he left the Evolution-Degeneration Ray Gun behind in the past, this advanced civilization came into existence. There, Nobita meets a dog named Hachiko who resembles Ichi. Hachiko tells everyone about his plight: his parents and others went to the Cat-Jera Paradise and never returned. Everyone decides to investigate Cat-Jera Paradise.