To Sketch a Sphinx (London League Series #6)

From the Hand of Sketch...

Henrietta "Hal" Mortimer has been working with England's operatives and spies for years, her remarkable memory and artistic talents invaluable to many missions. The last thing she expects is to be pulled into a field mission herself, and to be partnered with the most insufferable asset she has ever met. Worse, then, that she has to marry the man.

And the mind of Sphinx...

There are very few people who rattle John Pratt, gifted code-breaker for the Crown, but Hal Mort...