The Dumbfounded Doctor is the 47th chapter of the Dr. Slump manga. It is the sequel to "The Happy Doctor" and "Zippity-Doo Doctor".
Summary[]
The group returns to Earth
Senbei Norimaki, Midori Yamabuki and the kids are returning back to Earth after their trip in outer space. Midori still is very upset by the events of the previous chapter, but Arale Norimaki happens to lighten the mood by farting. In front of the Norimaki Residence, the gang meets an old man who happens to be Taro Soramame, soon joined by an elderly Akane Kimidori and a boy who states that he is Peasuke's grandson Pasuke. They wonder what the group is doing in front of the residence and say that Senbei Norimaki disappeared 50 years ago with his little sister Arale Norimaki, Gatchan and Midori Yamabuki. Afraid, Senbei has the idea to use the Time Slipper to go fifty years in the past. It is then revealed that the elders were the actual Akane and Taro portraying older versions of themselves and playing this joke as revenge over Senbei who did not take them for the space trip.