The Matthew Hervey series continues to get better in this novel. I'm not sure if he planned this all along, but Mallinson fills much of this novel set in and about 1826 Portugal with Hervey's memories of 1808 Portugal (the retreat to Corunna, in particular).
This feels kind of like a copout - an easy way to pad out a series - but not actually because it's bad or anything. More because it felt like he'd intentionally started with Hervey well begun on his career, that these early years were not so important. On the other hand, the naive Hervey of 1808 is definitely interesting to compare to his world-weary self of 1826.