Love, love, love this series. Hot romance, great humor, suspenseful plots - it's pretty much exactly what any woman needs on her shelf for rainy days. 'The Spy' is the third book in The Liar's Club series, featuring a group of men working as undercover agents for the Crown (and the Royal Four, but that's a whole other series). The main cast of characters interact with each other throughout the whole series, so it does help to read them more or less in order.
It is finally Liar James Cunnington's turn to fall in love. What he doesn't realize is that Phillipa Atwater, the woman he is destined for, is currently masquerading as a young man - the tutor he has hired for an adopted street kid. James has been charged with tracking down a missing codebreaker who is suspected of turning traitor and joining Napoleon's forces. The codebreaker happens to be Phillipa's father, and Phillipa also suspects James of nefarious deeds.
While in her guise as a young man, Phillipa falls in love with James and finally figures out a way to show him her love by using another disguise. When James finds out what and who she is, all hell breaks loose.
This is actually my least favorite book in the Liar's Club series, but that really isn't saying much. Plenty of action and romance and humor, and the suspense story that began in book one is continued which good character development along the way. Very enjoyable read.