Books like The Watchmaker's Daughter (Glass and Steele) by C.J. Archer

Agent of Byzantium is a historical fiction novel by Harry Turtledove that blends imaginative storytelling with historical context.

They are each other's fiercest love, greatest danger, and only hope. Séverin and his team members might have successfully thwarted the Fallen House, but victory came at a terrible cost -- one that still haunts all of them. Desperate to make amends, Séverin pursues a dangerous lead to find a long lost artifact rumoured to grant its possessor the power of God. Their hunt lures them far from Paris, and into the icy heart of Russia where crystalline ice animals stalk forgotten mansions, broken goddesses carry deadly secrets, and a string of unsolved murders makes the crew question whether an ancient myth is a myth after all. As hidden secrets come to the light and the ghosts of the past catch up to them, the crew will discover new dimensions of themselves. But what they find out may lead them down paths they never imagined. A tale of love and betrayal as the crew risks their lives for one last job.

A French mystery tale of a young girl who stumbles upon an ancient Grail labyrinth.

In the presence of mine enemies