Ok. I know I'm a geek when it's making me squee to give someone Apocolypse Door as a Christmas present. (again. Gave out two copies last year.)
But really, these stories are like the Urban Fantasy version of what Dan Brown should have done, only with a lot more wit and humor.
Peter Crossman is a Templar and a Priest, and that Order Militant is still alive and still guarding those treasures which are too dangerous for humanity, and guarding humanity from the minions of Hell, acquiring the powerful objects which aren't yet possessed by the church before Hell takes advantage. In this book, he is sent to find a group of UN observers who seem to have gone astray, been traced as far as New York, and then disappear. His partner is a Sister of the Poor Clares who is far too knowledgeable about weaponry and bespoke Italian leather suiting (she's been sent to kill him). There are also aliens, holy occurrences that in other circumstances might be termed "magic", and walk-ons/drive-bys/drop-ins from various other pieces of the Christian mythos.
I will say the book feels like it suffers "first book" syndrome (a little stilted, the pacing isn't quite right), but that may be because I have read a lot of the author's later works and enjoyed them immensely. But this is perfect for anyone who geeks out about history, church legend/mythology, and likes some humorous fantasy.
On the other hand, if it sounds really good, please don't buy it before Christmas?
(yes, this is the source material for my character for Bel Noir. It's so much *fun* to play her!)