In 1890s Paris, a librarian and a detective must track down a killer - before the city goes up in flames. The Mortal Word is the enthralling fifth instalment in the Invisible Library series from Genevieve Cogman.

A corrupt countess. A spy in danger. And an assassin.

Peace talks are always tricky - especially when a key diplomat gets stabbed. This murder rudely interrupts a top-secret summit between the warring dragons and Fae, so Librarian-spy Irene is summoned to investigate. With her detective friend Vale, she must track down the killer - as peace hangs by a thread.

Accusations fly thick and fast. Irene soon finds herself in the seedy depths of the Parisian underworld on the trail of a notoriously warlike Fae, the Blood Countess. However, the evidence against the Countess is only circumstantial. Could the assassin - or assassins - be closer than anyone suspects?

Continue the witty and wonderful series with The Secret Chapter.

Praise for the series:

'I absolutely loved this' - N. K. Jemisin, author of The Fifth Season

'Irene is a great heroine: fiery, resourceful and no one's fool' - The Guardian

'Cogman keeps upping the ante on this delightful series!' - Charles Stross, author of the Merchant Princes series