Human beings are bad at processing time. We think of time relative to our own existence, where a year seems long. But on a larger scale, a year, a decade, even a century, can be as nothing. We struggle to even conceptualize this. If something has lasted say, ten years, we’ll say, “It’s been that way forever.”

Which is why a book with a non-human protagonist is so tricky, and why this book, told from the perspective of an oak tree, makes for such an interesting exercise.

The story begins with Catherine Miller, a young doctor murdered in 1853 shortly after her graduation from medical school. She never knows who murdered her, but her spirit mysteriously lives on inside a oak tree. From this vantage point, she witnesses the changes that occur over the centuries, as a technology evolves, cities rise and fall, and human nature remains in many ways the same. In the present day, Catherine’s consciousness inhabits the backyard of a cruel man whom she sees murdering another medical student.

She does what she can to help the authorities in solving the crime to which she is the only witness. But as a tree, she has limited ability to communicate with humans, which is where the implacable veteran police detective Lani Whitaker and her partner come in to the picture. The book alternates between Lani and Catherine, between past and present, giving us a full scope of what changes, and what remains.

Sorry to inflict my amateur literature teacher routine on you two weeks in a row, but this book has a theme, and that theme is age. Besides the obvious point of the Catherine-as-oak’s many decades, Whitaker is also confronting a more human experience of time, as she is near the mandatory retirement age, and is reminded of it constantly.

The book has a very melancholy feel to it, and not just because of the multiple murders that drive the plot. It’s about people observing the passage of time from a variety of perspectives. The vibe of the book is the same vibe you get from a tree in late Autumn, and obviously that’s exactly what it should be. It’s a work of magical realism with a motif that goes beyond the typical police procedural elements to evoke a bittersweet longing for things we can’t even remember.