I was hoping for some good laughs from Black Knight. I did laugh a bit, but overall, this is not a very good movie. At times, I can set everything aside and enjoy a mindless comedy for just what it is, mindless entertainment. Other times, I need more.
I guess this time I just wanted more.

Martin Lawrence plays Jamal, a castle themed attraction employee who suddenly finds himself in the days of real castles, knights and kingdoms. Through that over used plot device known as mistaken identity, suddenly this street smart urban guy finds himself as part of the king's court.

I like Martin Lawrence, but he's so much better than this cookie-cutter comedy. He's basically reduced to being one of those caricatures whose facial expressions, and brief reaction shots ("damn!", and "oh shit!") dominate the movie.
And what the hell is Tom Wilkinson doing here?
Yeah, he was in the first Rush Hour and The Patriot, but he also does smaller, more significant movies. This'll be one to leave off the old resume.

If you can just go ahead and enjoy some mindless fun, you might enjoy this movie.
Just don't expect too much, OK?