This is a historical adventure story, about a young monk in thirteenth century England. He gets drawn into some dangerous plots and ends up joining a crew of relic smugglers, and thus on to more adventures with them.
The book appears to be intended as the first in a series, and so spends a fair amount of time introducing characters. Despite this, it's a good novel in its own right - the protagonist's Campbellian hero's journey, in fact.
There's lots of neat historical pieces too - from the plots regarding stolen and faked religious relics, to the hints of conspiracy to come (key characters are exiled Cathars, and there's a Templar and a Byzantine princess in there too).
Overall, a good adventure story and I look forward to the next one.