The Witch Tree by Tana French is a remarkable novel for a number of reasons. One is that she manages to tell the entire story, all 528 pages of it, in the first-person voice of Toby and maintain the reader's interest.
Toby, like other characters in the novel, is unreliable, and French is fascinated by unreliable narrators, “because I think that one of the core points of the arts is to give us a glimpse of what it’s like to be someone else, to see the world for a little while through someone else’s eyes, and to realize that other people have viewpoints that are completely different from our own, and that those are just as real and intense and vivid and valid."
Continuing to make her point in a New Yorker interview, she said. "And—this is going to sound odd—but I think an unreliable narrator does that best, because we are all unreliable writers of our own lives. We all reshape our own narratives to make them fit what we want to believe or what we need or just what interests us most. Like, if you’ve got siblings, and the two of you tell a story about some argument that happened in your childhood. You’re gonna get two completely different versions of that argument, because both of you have shaped the narrative to fit what suits your thoughts best.
"If you’re reading an unreliable narrator, that’s what brings you closest to the person, because you’re not seeing their experience objectively. You’re seeing it the way they see it, which is through their thoughts, through their biases, through their needs and their fears and their desires. So I think an unreliable narrator is the one you know most intimately, ironically, and the one who comes closest to fulfilling what the arts are really for.”