The Archivist and the Knife. Phoenix Empress, #1

Refusing to accept a position under her childhood rival, Samira opts instead to leave the Tindersands Family and take on the role of Imperial Archivist. Thrown out of her home for her betrayal, she must learn more about the role she chose in anger. What had once been an important position, has languished in the decades the Phoenix throne has lain empty. Tajamar can't understand why she would throw away all she's worked towards because he was chosen first.
The golden boy of the Tindersands Family, Samira is the only person to ever challenge him or get on his nerves. Happy the thorn in his side has left, he looks forward to enjoying the favour of his new position. Meanwhile, servants turn up missing their shadows, ignored by the five families battling each other for supremacy in their Council. The empty throne looms as the prize over them all. Both Samira and Tajamar hunt for an explanation.
Can they trust each other for long enough to bring the truth to light? Exploring the hidden archives, Samira must draw on all her skills to weave a way between the familial politics, crystal magic, and uncertain alliances. Finding herself at the centre of a conspiracy, she must call on friends and enemies to help save the Empire. Before stories that should never have been forgotten repeat themselves.