The Gallagher Girls resume their typical lifestyle: that is, spying, training, fighting, etc. But outside their school lives, there are their social lives.

It's sophomore year at Gallagher Academy for Cammie, Bex, Liz, and Macey, and everything seems perfectly normal. That is, until their lives become intertwined with the lives of the boys at Blackthorne. Romantic sparks ignite despite the pressing matters of life and death that are omnipresent in the life of a spy.