Ottoline is back in a brand new adventure! Ottoline and Mr. Munroe love puzzles, clues, and mysteries. One day, they meet an enigmatic purple fox, who offers to take them on a night-time urban safari. The fox shows them all the hidden animals of the city and Ottoline makes notes on them in her field notebook. Mr. Munroe is making notes, too--on the anonymous poems he finds stuck to lamp posts on their journey. Who is the secretive poet, and how can he and Ottoline help them mend their broken heart? Includes a fold-up-and-keep fortune teller!