My 20 year old son and I saw Dark Knight last night at midnight. It is a dark movie with a compelling performance from Keith Ledger. It is not appropriate for children under 10-12. For a 2 1/2 hour movie, we were focused on the movie throughout. As we talked on the ride home, we agreed that this was definately a 5. It is relatively rare that we will agree on such a strongly positive evaluation. I suspect that my son is trying to figure out who he will go with to see it again. We have seen earlier Batman movies, and this is a complete departure from the earlier and much lighter fare.