The way the novel was told was interesting (and sometimes long-winded). We see through the eyes of Tony, Charis and Roz, but never through Zenia's. She remains a mystery until the end.
The novels starts out on the day the three friends see Zenia after years (and thinking that the woman is dead and cremated). We see that day through each of the three women's eyes, what they did leading up to, etc. Then, we find out each of the three women's history with Zenia, how she intertwined herself into each of their lives.
What was masterfully done, is that as the friends (separately) confront Zenia at the end, we still don't know about the woman. We don't know what she's said was true or what was made up. She's an enigma, a sociopath, a compulsive liar. There was absolutely nothing good about the woman.
The characters of Tony, Charis and Roz are interesting. They are all completely different people, but are united because of Zenia. Otherwise, they might never have been friends. They meet often for lunch, having formed a support group of sorts.
They are a bunch of side characters, but they're not as fleshed out. Basically, it's the story of four women. It's about relationships between women, the good, the bad, and the ugly. The Robber Bride is a fascinating portrayal of how one person can come into our lives and completely turn it upside down. It's a great character-driven story. At first, I didn't know if it was going to be worth it, but as I got into the women's backgrounds with Zenia, I became engrossed. I couldn't believe the character of Zenia. I hope I never come across a Zenia in my life.