Royal Blood — Simon Rose

The Stone of the Seer is an exciting historical fantasy series of adventure novels for young adults, primarily set in the turbulent era of the English Civil War.In Royal Blood, book two in the series, Lady Elizabeth Usborne, Kate, and Tom, along with the tempus inspectoris and the mysterious black Viking stone, are in the heart of London in early 1649, as King Charles prepares to face his accusers at his trial in Westminster Hall, while Elizabeth, Kate, and Tom desperately attempt to evade capture by Daniel Tombes, the witchfinder.