As the youngest and only female member of the Knights Templar, Bilquis SanGreal grew up knowing she wasn't normal. Instead of hanging out at the mall or going on dates, she spends her time training as a soldier in her order's ancient battle against the Unholy.

One of the order's ancient enemies has resurfaced, searching for a treasure that the Templars have protected for hundreds of years -- a cursed mirror powerful enough to kill all of London's firstborn. To save her city from catastrophe, Billi will have to put her heart aside and make sacrifices greater than any of the Templars could have imagined.