Queen's Men, The (Agents of the Crown #2) by Oliver Clements; 2021. Hardcover.

As she travels through Waltham Forest, Queen Elizabeth I is ambushed by masked gunmen who leave her carriage riddled with holes before disappearing into the night. The queen searches for the ultimate weapon to protect her country and throne: Greek fire, the recipe of which disappeared with the collapse of the Byzantine Empire. She orders her friend John Dee - scientist, philosopher, and spy - to rediscover this vital secret, despite his misgivings. Dee's mission to secure his nation's future may prove impossible, unless he deploys the most effective weapon of all: intelligence.