The book upon which the movie is based easily makes it onto my all-time favorite list, but the movie, although there were elements I found enchanting, is forgettable. For the short list of things I liked: they did quite a good job casting the character of Rhiannon; she was charming and believable. I liked the song that replaced Kate Bush's "Running up that Hill" (which is a great song!), and I appreciated being able to see how A embodies other people.
However, the movie does a considerably poor job taking on the serious themes of love and identity that underlie A and Rhiannon's love story. The book is an easy read, but it takes on profound questions, such as "Are we humans first, or souls first?", "Who am I?" and "Why do we love who we love?". Moreover, about halfway through the movie, it diverged completely the book in order to close the story arc in its neat 90-minute time frame. While it the book Rhiannon's skepticism about getting involved with A persists throughout, the movie assigns her the task of convincing A to attempt to outlast the 24-hour timetable he had previously believed to be inviolable. In the book, it was a plot twist when A discovered that the Reverend was also a host to another spirit like A. The movie erased this sinister subplot of Reverend Poole and Nathan entirely.
All in all, do yourself a favor and skip the movie but read the book, stat.
All in all, do yourself a favor and skip the movie but read the book, stat.