(He of the bad back is blogging whilst recumbent on the floor; bless his little heart. It's not that easy either.)
If you're looking for a good summertime read, you could do much worse than Dan Brown's Angels & Demons. It's Brown's other book, actually written prior to his mega hit, The Da Vinci Code.
Without trying to give too much away, let me say that the two books follow the same formula: so much so that, in a sense, if you've read one, you've read the other. Both feature protagonist Robert Langdon, an academic and expert in religious symbology, and in each he is aided and abetted by an attractive lady of genius intellect. While the two female co-protagonists share similar intellects, looks, and personalities, their academic specialties differ to suit the plot. There are numerous other similarities as well. Both involve the Catholic Church, highly powerful and secret organizations, fast-paced plots, very condensed time frames, infiltration, and treachery.
Of the two, I prefer Angels & Demons. I found it very difficult to entirely suspend my disbelief in The Da Vinci Code. My main stumbling block was Brown's theory of The Chalice; it was a rather gargantuan stretch for me. However, any book of this type requires suspension of belief, and I was better able to go with the flow in Angels & Demons. While light and frothy in a sense, it is also very cleverly and shrewdly contrived ... as is, despite my reservations, The Da Vinci Code.
If you are one of the ten people on the planet who hasn't yet read this novel, and if you are in the mood for a fast-paced romp through Rome and the Vatican, you should adding Angels & Demons to your nightstand collection.