The second book of the Frostborn. Spoilers ahead.
For instance, Ridmark is traveling with Kharlacht when they are attacked by beastmen and hear accusations of kidnapping. Caliande and Caius chase after.
It's when the first two encountering a young man, and undead kobolds attack the second two, that the story picks up with a menace in the land, unknown to all inhabitants, except in its effects, which they blame on the wrong people.
It goes on with a stepmother, Calliande's having an authority she didn't know, from the past, a senile old woman, sneaking in behind a waterfall, a new way to fight with magic, a knight in pursuit of a wyvern, and more.