“Are there four separate but not equal antagonists, or one antagonist and three minions [in The Devil in Nita Dodd]?”
There’s always only one main antagonist in a classic linear story because you can only have one climax with the obligatory scene of the protagonist and the antagonist facing each other in final battle.
But you can have subplots that the protagonist and (in this case) her team* have to clear out of the way to get to the Big Bad. In the best of all possible worlds, you have one main antagonist and a couple of subplots that aren’t life or death, say family or work. In this case, which I do not recommend, I ended up with five different factions fighting for different things: