Sovereign — C.J. Sansom

Autumn 1541. A plot against the throne has been uncovered, and Henry VIII has set off on a spectacular progress from London to York, along with a thousand soldiers, the cream of the nobility, and his fifth wife, Catherine Howard, to quell his rebellious northern subjects. Awaiting his arrival are lawyer Matthew Shardlake and his loyal assistant, Jack Barak. In addition to processing petitions to the king, Shardlake's task is to protect a dangerous conspirator until he is transported back to London for interrogation.

But when a local glazier is murdered, things get a little more complicated as the murder seems to be not only connected to Shardlake's prisoner but also to the royal family itself. Then Shardlake stumbles upon a cache of secret papers that throws into doubt the legitimacy of the entire royal line, and a chain of events unfolds that threatens Shardlake with the most terrifying fate of the age: imprisonment in the Tower of London.