Mysterious Villains

Poul Anderson's characters may be in conflict either with human or alien villains or with their natural environment. There are perhaps three ways to introduce a villain:

(i) we are told from the start that this character is the villain, e.g., Brechdan Ironrede in Anderson's Young Flandry or Ernst Stavro Blofeld in Ian Fleming's Thunderball;

(ii) an apparently innocent character turns out to be the villain, e.g., Aycharaych in Anderson's The Day Of Their Return;

(iii) a mysterious background figure or secret mastermind is eventually identified, e.g., Number One in the James Bond films or in The Prisoner TV series, Andy Diggle's Max or Stieg Larsson's Zala (see Blofeld's Successors).

Two Observations
Larsson's gradual disclosure of Zala and even of dark forces behind him is masterful.
I don't think that Anderson does (iii)?