Great source material but screenplay was poor
Childhood's End was a great novel, and a short one. But the screenplay was padded out with all sorts of irrelevant nonsense that didn't add anything and often was either abandoned or just not properly explained, and it did a p**s poor job of explaining what the overmind really was and what was actually happening to the children - ie the core of the story! Didn't do a great job of explaining the overlords appearance either.
On the plus side, Charles Dance made an excellent Karellen.