Night's Masque, book 3: The Prince of LiesAnne Lyle2013

Elizabethan spy Mal Catlyn has everything he ever wanted—his twin brother Sandy restored to health, his family estate reclaimed and a son to inherit it—but his work is far from over. The renegade skraylings, the guisers, are still plotting; their leader Jathekkil has reincarnated as the young Henry Tudor. But with the prince still a child, Mal has a slim chance of destroying his enemies while they are at their weakest.

With Sandy’s help Mal learns to harness his own magic in the fight against the guisers, but it may be too late to save England. Schemes set in motion decades ago are at last coming to fruition, and the barrier between the dreamlands and the waking world is wearing thin…