Heavenly Design — Mac Flynn

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The first novel in the three-part Angel Fable arc.

Jane and her companions decide to enjoy the Shifting World for once, and find themselves fortunate to arrive in time for the Festival of Gad, a joyous time of celebration held every four years in honor of the prime deity of the world. Unfortunately, their vacation plans are burned to ashes when one of the ceremonies is lit aflame under suspicious circumstances.

Worse still, Jane keeps seeing a man dressed not the plain clothes of the Shifting World, but in dark attire worn in our realm. He looks straight at her without blinking, and she has a creeping feeling that he can see more than what's on the surface.

When she's confronted about the truth of his identity, her world gets a little more complicated, and dangerous. Now Jane and her companions must help stop a dark plan to lay waste to the festival, or die trying.