I thoroughly enjoyed this book - it was fast paced, enticing and full of intrigue. I was an instant fan if the main character Lex, she was likeable and relatable, yet in a completely different world as part of the underground MI6. Her struggles balancing work and motherhood, doubting everything she was doing was reassuring, mixed with the intrigue of finding out who was the snake, and how to thwart their plans. The only reason I didn't give 5* is because I head a hunch pretty early on "whodunnit", but that said I couldn't work out how or why, so I didn't lose interest. I'm also not sure if this is a sequel; it doesn't matter if it is, as it's a strong stand alone story, but there were a few references to things I felt I should know more about. All in all definitely worth a read!