Spies in St. Petersburg: Katherine Woodfine

With Sophie still missing in action after their explosive mission in Paris, Lil decides to take matters into her own hands. On a new mission for the Secret Service Bureau, can Lil find Sophie in misty, mysterious St Petersburg?
Can they uncover the identity of their true enemy and can they trust anyone - even the Bureau?
It's time for Sophie and Lil to put their spy skills to the test.