Rather bland overall. Not bad, but not good.

Rating: 6/10 (30 November 2015)

I would hesitate to say that this adaptation is similar to the book. If you're talking in terms of events that occur, yes it's the same story. But in terms of theme and overall feel and effect it's very different. Some of this was inevitable, but not all. What I thought was great about the book was the mystery and revelation of the Illuminati path and the who and why of the whole anti-matter plot along with the debates over religion and science. The book was so intriguing, or so it seems to me, because of it's complexity and extensive setups for the big payoffs. But you can't fit all of that into a two-hour movie, so the result was a few chopped scenes and plot threads, which made the movie suffer. We saw this when Eragon was made into a movie and a few parts of the story were slapped together into something that sort of resembled the complicated novel. With Angels and Demons, the result is a rather bland movie. There's no emotion from the characters and the fast pace reduces the suspense. It's like a historical, though dramatic, portrayal of the events of the book. Usually it's the inverse as with classics, where the actors and director give more life and complexity to the characters from the book. In this case, the filmmakers also decided to make the safe, some might say cowardly, decision to chop most of the science vs. religion debates from the book. I can understand that the studio and other people involved didn't want their name on anything that could be construed as propaganda, especially since people tend to forget about the disclaimer that the studio doesn't necessarily agree with whatever they're showing has to say. Granted, the book had its flaws, mostly in being predictable and stretching plausible reality at a couple of points, but at least it was interesting.
Robert Langdon, Vittoria, Olivetti, the camerlengo, the assassin, the presiding bishop, and the head of the swiss guard are all in the movie. The only significant character that isn't included is Maximillian Kohler. The characters are much different than in the novel. They have much less personality, with the possible exception of Langdon, and have next to no motivation even the camerlengo. Most of the camerlengo's spirited beliefs about blending science and religion and not being enslaved to one or the other are gone, even though he has the same revelation about planting the antimatter. Langdon comes off as a more active character than in the novel, but he has no more depth than the other characters.
For those who haven't seen it, the plot is fairly interesting. With little time to process everything while watching the movie, it might get a little confusing. So you may want to read a summary and watch a trailer before watching it and take notes on the plot. It's good to have at least some background knowledge of catholicism. I wouldn't say that you have to be a catholic or Christian to understand it, but just keep in mind that there is some religious history involved.
The technical execution isn't anything special, but the movie looks nice. The fiery contrast of colors adds to the dramatic feel along with the sound effects and lighting and score. But it's not shot superbly and the acting is standard; definitely not bad, but not good either.
I would recommend this more to people who haven't read the book but might want to. Without knowing the plot twists and such, the movie might have a greater effect on non- readers. To those who have read the book, I wouldn't anticipate that it will affect you too strongly outside of being disappointing. It's somewhat entertaining. I'd rather watch it than not, but I'm in no rush to see it again either. So it might be worth your time to set aside a night or two for it, but don't expect to be wowed. Just a couple of closing remarks: you don't have to have seen Da Vinci Code beforehand and in case I didn't fully address this earlier, you don't have to worry about having any religious beliefs, your own or anyone else's, attacked or anything like that. Overall Rating: 7.4/10.