The 1970's was not a good time for the Disney Studios. Much of the stuff that came from Disney at this time were corny and fluff. This movie however is a rare exception, esp. for it's time.
This film is about a bother and sister, Tony & Tia (Ike Eisenmann and Kim Richards)who have powers(ESP, Levitation and the like)but they don't know how or where these powers come from. Tia is being bothered by memories of an accident that she can't piece together. However, as the film progresses-the pieces come together like a puzzle and they figure out the answer to the question: "Where are we from?"
I must say that the chemistry between Eisenmann & Richards worked so well, people actually believe that they are brother & sister. It's really remarkable how well they worked together-no wonder it looked so real. This is remarkable acting talent on the part of these two and no one could have done it better. This is why I think these two actors are underrated.
I'm not going to go into detail of the rest of the film. Read the other reviews for that. One thing I need to mention is that the special effects were great for it's time. Maybe They were a little Cheesy, but the essence of the story is not the powers these kids have, but they are searching for their home and looking for answers about where they come from. To me, this is the real story-not the special effects.
I just got my DVD copies of both films This and "Return From witch mountain" They done a good job remastering the soundtrack in THX, 5.1 Dolby surround sound. It sounds as good as it does in the theater if you have a home theater system.