Codes to crack, puzzles to solve, mysteries to uncover - there is never a dull moment in the life of a spy. And that is exactly what Mickey does: she is the only human operative in the secret animal spy agency COBRA. Mickey's previous adventures with the Animal Spies proved she is not only smart but also trustworthy - it's a great honour for Mickey, as the Animal Spies do not work with humans. But when human spies start disappearing under suspicious circumstances, Mickey feels it's her responsibility to discover what is happening. In Mickey and the Missing Spy, it is up to Mickey to unite the human and animal world of espionage for the very first time, in order to save her hero and top spy, Hildegarde McTavish!