Here’s a movie that would seem to have everything — stirring story, wonderful actors, acclaimed director, noble message. However, it could have used a little subtlety. That quality served director Charles Burnett well in earlier efforts (Killer of Sheep, To Sleep With Anger) but is lacking in this Showtime movie about a young slave girl (spunky Allison Jones) who learns that knowledge is her only power — thanks to brave Nightjohn (Lumbly), whose will cannot be broken even by the cruel whip of master Bridges. With the exception of Bridges, the talent assembled for Nightjohn deserves a more honest vessel. Viewers over the age of 12 are likely to agree.