Ron Howard got some great movies under his belt and Tom Hanks is one of my favorite actors of all time. A combination you can't miss when it comes to choosing a movie.
Yes they had all the right ingredients to have a great movie, but honestly they really failed in what Angels and Demons succeeded. The pace of the movie was very slow you would almost fall asleep and the elasticity of the story as it's shown on the screen unneeded and made the film dull.
As usual Tom Hanks did a good job reprising the role for the third time as felicity jones who was great in her role as the antagonist. Directing wise Ron Howard was decent not like the great work he did on beautiful mind and other movies.
So in a nutshell where the performers succeeded, the screenplay was made long and here comes the responsibility of the main producers Brian Grazer and Howard who should have taken executive decisions to shorten what seemed way too long.