247. "Superman: The Return of Superman's Lost Parents!", "Tommy Tomorrow: Tommy Tomorrow, Space Convict X-146-93", "Congo Bill: The Riddle of the Super-Zoo!"

One day while reading in his apartment, Clark Kent is alerted to some commotion outside of his home. Going outside he is astonished to see a time machine piloted by Ma and Pa Kent, who apparently have come from the future to visit their grown-up adopted son.