The Fires of the Gods. Akitada Mysteries, #7

The capital is plagued by unexplained fires, and panic threatens to break out, but Akitada has his own problems to worry about.  His ailing wife expects a child and he loses his job to a political appointee. When he tries to confront the nobleman who is responsible for his dismissal, he ends up suspected of his murder.  With no income and a growing family to support, Akitada desperately plunges into the investigation of this crime and a search for a missing youth, while Tora tracks a gang of young arsonists.
 These seemingly unrelated cases converge, and before Akitada can uncover the sinister plot behind the fires, he almost loses his own life and those of his wife and newborn child.