Paper And Fire (The Great Library #2) by Rachel Caine

In Ink and Bone, bestselling author Rachel Caine introduced a world where knowledge is power, and power corrupts absolutely. Now she continues the story of those who dare to defy the Great Library—and rewrite history…
 
Jess Brightwell has survived his introduction to the sinister, seductive world of the Library, but serving in its army is nothing like he envisioned. His life and the lives of those he cares for have been altered forever.

Embarking on a mission to save one of their own, Jess and his band of allies make one wrong move and suddenly find themselves hunted by the Library’s deadly automata and forced to flee Alexandria, all the way to London.

But Jess’s home isn’t safe anymore. The Welsh army is coming, London is burning, and soon Jess must choose between his friends, his family, and the Library, which is willing to sacrifice anything and anyone in the search for ultimate control…