Book 2. Massive spoilers ahead for The Dragons of Dorcastle.
It opens with our intrepid pair discovering that their separation at the end of Dragons was not enough to protect them. After some trouble with an assignment, Mari is ordered into a place collapsed in anarchy. And Alain is ordered as the sole Mage in a military raid. After the events of the last book, he asks questions enough to establish that he was lied to. And they discover trouble
Mari goes somewhere else. As a consequence, she and Alain meet again. And the rest includes a forbidden device, killing a dragon, a roc attacking a train, a dead city and its secrets, a blizzard and passing as an eloping couple, some failures to communicate being fixed up (with strong reactions) and more. Consequences are building. So is the foreseen (and metaphorical) storm.