Book 4 of Olympians, Hades: The Wealthy One is a bit more like Zeus in its structure, in that it principally tells one big story (in this case, the abduction of Persephone) rather than a tapestry of interconnected tales, as in Athena.
It may be Hades who gets the title nod, but he really shares the starring role with both Persephone and her mother, Demeter. Of all three main characters, until this point in the series Demeter has gotten the most panel time, as it were, but only as a supporting or background character. As a result, I've spent a lot of time sketching the beautiful Goddess of Grain in a wide variety of moods and poses, as she really gets put through the emotional ringer in this book.
The first step when I'm writing a book is to fill up some sketchbooks with "key Scenes" that may or may not make it into the final version. Here are a few sketches of an enraged and distraught Demeter, including an action shot of her in her role as Demeter Khrysaor, or Demeter of the Golden Blade. Looks like she's pretty miffed at Zeus. I wonder why?