The story of Ellen and William Craft is great, but the writing of this book is terrible.
In one paragraph the author words things as if she can't speak with certainty, because she wasn't there and couldn't truly know. The very next paragraph she words things with such certainty, it's like you are reading a completely different book. It got exhausting. If she picked one style and stuck with it, it would have made the book so much better.
Their story is a good one, just told by another author.