Monstrous Allies. The Charm Collector, #4

Sometimes your best ally is your worst enemy. Harlow, Camila, and Caspian finally head to the Collective's Tower. Though Sorceress Rhiannon bought them some time, stalling time is over. The sorcerers need each of them for different reasons, but all three fear that once they walk in, they're not getting back out.  For years, Felix Turner has been searching for the truth about Naomi West's murder and how it's tied to the death of Nelson Fletcher.
When someone from Naomi's past returns to Luma with a new lead, Felix is determined to get to the bottom of the mystery once and for all. Kayda's guilt over failing Kessler has given her a bit of a savior complex. When another remote hub is attacked by ferals, she refuses to let more innocents suffer on her watch. Diving headlong into this new mission, however, sends her far from home-and reveals that the Shades' influence has reached far beyond Luma. Renata Bernard had no skin in this game only days ago.
Hells, she hadn't even known the game was being played. Now, not only has she been pulled into a scheme Lachlan Shade hatched while in exile, she's also been pegged as the key to his success. She never would have thought being a scientist was this dangerous. Pulled away from friends and family, they all must forge connections with monstrous new allies-from sorcerers to aves to vampires-because everything leads back to Lachlan Shade. The Shades' leader has finally returned to the earthen realm, eager to begin The Restoration.
The Collective thwarted his efforts decades ago, but now, with his own monstrous allies and their feral minions on his side, he'll reshape the world . or take it down with him.