Okay, first of all, the quality of my print of this serial from Alpha Video isn't the greatest,
and the sound is often bad. And, well, it's pretty slow going. I don't know that much about
Chandu.
The character was popular in radio dramas in the 1930s and 40s. American-born Frank
Chandler learned occult secrets from a yogi in India, including astral projection, teleportation,
and the casting of illusions. And, oddly enough, Béla Lugosi played the main villain in first
movie. Here, he is recast in the title role as Chandu (because apparently the original actor
was boring as hell). In this serial, Chandu has a magic ring, is able to consult telepathically
with the yogi to ask his advise, he teleported once in the first Chapter, and was able to turn
himself invisible once. But, oddly enough, he doesn't seem to be able to do it later on, and
he needs the help of a White Magician (that he saves from a prison cell) in order to turn
invisible later on. I think it was explained that when Chandu is on the island of Lemuria,
there's so much Black Magic protecting that place that he has greatly diminished powers.
I kind of dozed off a lot during this one.

Initially, it seemed to me that Chandu was a protective fatherly-figure to Nadji (played
by Maria Alba), but, by Chapter 5, she's his fiance. It really came as no surprise to
me to see that this serial was later cut into two movies: Chapters 1–4 ("The Return of
Chandu") and Chapters 5–12 ("Chandu on the Magic Island"). The first portion involves
Chandu besting the High Priest Vindhyan (Prival) and foiling his plan to sacrifice
Nadji. Then, thinking they are safe, Chandu, Nadji, and Chandu's sister (and her
adult son and daughter) decide to resort on whatever island they ended up on.
Then, at the end of Chapter 4 and the beginning of Chapter 5, you see that there is a
much bigger cult threat on the island of Lemuria. Nadji dreams of this, and Chandu
essentially looks into her memory of this dream to get an idea of what he's up against.
He then goes off alone to try to find the island. Meanwhile, Nadji is kidnapped and
taken to the island. Chandu arrives back home too late to stop this, so he--and his
mostly worthless tag-along family who insists on tagging along--charter a boat to go
to the island. When they get close, well, the evil baddies help their boat to sink.
After washing ashore, Chandu is soon separated from them, they get captured, and Chandu
ends up in some caverns filled with various threats like a man-eating tiger. Oh, and
did I mention that there's a small band of man-eating savages, and that they live on or
about those big doors used in the original King Kong movie? Well, they do....