For a fan of the series, this is pretty much like the manga. As far as I remember the only thing they added was an extra shot of the Undertaker smirking a bit near the beginning. I don't really recommend a newcomer to start with this movie, not just because of the on-going story, but because this movie is essentially only set up for future arcs.
Nothing is really accomplished in this arc alone, which doesn't make the story bad, but all the other arcs in the manga have a clear beginning, middle and end. Something is always accomplished and characters are developed.
In this arc we get to learn more about Ciel and Sebastian's relationship, but either of them really reflect upon it and it isn't really relevant for the story presented in this movie though they were interesting. In the Circus arc I think the flashbacks were done much better because they affected Ciel's actions towards the end and tied into the plot.
Nevertheless the visual in this movie were nice and the characters were enjoyable as always. The voice acting was good and the music pleasing. Black Butler fans will be pleased by it, but newcomers should start with the manga or first series anime.
