Pepura Hasake is living in a secret room after being fired from the museum due to his "solar sun", which powers the museum, once going out of control and endangering the world. Guide Kurt provides a tour and Doraemon and Nobita slip away to search for the bell. Using the magnifying glass and inference hat, Nobita determines that the culprit is Kaito DX, a well-known 22nd-century gadget thief.ĭoraemon, Nobita, and several of his classmates go to the 22nd century Gadget Museum. Nobita then has Doraemon produce the "Sherlock Holmes" gadgets. Doraemon is unable to obtain a replacement bell from his factory, so Nobita tries replacements which resemble the bell.
Doraemon wakes up and panics at his bell's absence. The robotic hand then steals Doraemon's cat bell and disappears into a time hole. Nobita accidentally throws it away while hiding a failed test paper from his mother. A robotic hand appears and leaves a "DX Card" on Nobita's desk just before Nobita returns from school.