Not really my type of film, but I gave it a shot anyhow, and must admit that Angels & Demons did not disappoint. Having not read the book, or really paying any bit of attention to this film's marketing, I had zero expectations going in. All I really knew was Tom Hanks is in the lead, Ron Howard is directing, and it's some kind of mythological / religious concoction. I'm going to assume that's all you know as well, and even if you know more you can still keep reading (or go fuck yourself for all I care).
In Italy, CERN Laboratories finds a way to capture antimatter, and put a small amount of it in three vials. Great! But wait...one of the vials is stolen! Oh no...in the wrong hands, antimatter could kill millions. That's right! What could be worse? Well, the Pope of Rome just died too! So now we have some juicy conflict. Physicist Vittoria Vetra (played by Ayelet Zurer) was part of the team that captured the antimatter and is looking to get the stolen vial back. From evidence intentionally provided by the antimatter thief(ves), it appears painfully obvious that there is a connection to the secret brotherhood of The Illuminati. The criminals want to get back at the church for years of oppressing The Illuminati, so they rig the antimatter to explode at midnight (which would easily wipe out Vatican City) and kidnap the four Cardinals who were front runners to succeed the deceased Pope.
Vatican police and Swiss Guard have met their match, so they call in Harvard symbologist Robert Langdon (Hanks) to help find the criminals. Langdon needs to work fast to prevent the antimatter explosion and because the criminals have warned they will kill one Cardinal (of the ones they kidnapped) every hour. He uses his vast knowledge of Vatican history, and studies of The Illuminati, to try and track down the criminals. Camerlengo Patrick McKenna (played by Ewan McGregor) tries to help the investigation where he can, and plays a pivotal role later in the film.
Tom Hanks is his usual self, but Zurer was pretty useless. Her character added absolutely nothing to the story, and she isn't hot enough to be stuck in solely for eye candy purposes. McGregor played a solid supporting role, aside from a pretty long & cheesy speech he gives to the Cardinals near the end. There were definitely some shady characters in the film, but I felt they made those characters a little too obvious with the use of evil noises. While there was some religion, it wasn't super heavy; it was more geared around symbols and mythology. I really enjoyed the nice use of lighting and music to set biblical tones and evil elements. From what I am told, the film kept basically true to the book, aside from some character interactions (i.e.: Hanks' & Zurer's characters form a love interest in the book, but not in the film).
Angels & Demons was not a bad way to spend two hours, and it's definitely a good date movie. You have good acting, and an active & interesting story. My biggest gripe was that the ending felt pretty convoluted, but not so much so that it ruined the movie; it just kept it from reaching it's pinnacle.