This movie is a somewhat fascinating exploration of the theme of spirituality versus dogma. Based on a true story, Kardec follows the trials and tribulations of a professor skeptical of paranormal activity who becomes the leading proponent of "Spiritism" while finding a beautiful message concerning the past, present, future, life, death, and the afterlife that seems to contradict everything the dominant Catholic Church espouses. The acting is very good, and the costumes and sets capture a sense of mid-19th century Paris at a time when Europe was in economic, political, and religious upheaval.
Where Kardec falls short is in the story itself. Quite a few storylines dead-end or simply fizzle out. For instance, throughout the movie, two shady looking men seem to be following Kardec wherever he goes, but any potential conflict in this situation ends up as something else entirely. Some of the movies' themes don't really get the time they need, but are simply addressed in passing, or shoehorned into a Kardec diatribe before moving on to the next theme. It bogs down what might have otherwise been an excellent movie. Instead, Kardec is good, but not great, and interesting, but inconsistently so.