“Key of yellow metal” is a book by the famous writer Max Fry for those who like to unravel the secret ciphers hidden in ancient signs and objects.The protagonist of the book is 33-year-old Philip Karlovich “a free man of the world ”, which has the opportunity to relax, travel around the globe and be bored. But one day Philip's life turns upside down. Something happened that he did not even suspect. And it all started with a simple request from his father Karl, who, leaving on tour with a concert, asked Philip to bring him one little thing from Prague - the key to the secret room in his old apartment.The fact is that Philip's father obsessed with collecting old keys since childhood. He always believed that you can always find a door that fits the key from his collection. And in some cases he succeeds. But here's the paradox: in his own house there is a mysterious door to which there is no key. And unexpectedly, on one of the collectors' sites, he meets a man from Prague who claims that he has the original key to Karl's door. Philip goes to take the key, and suddenly gets into fantastic bindings.Connoisseurs of Fry's work will easily notice parallels in the plot of the book with Alexei Tolstoy's fairy tale "The Golden Key, or the Adventures of Pinocchio": a key made of "yellow metal" , mysterious door, name Carl. They also recognize other characters: a girl with colored hair, her friend who can turn into a dog (Malvina and Artemon)| a guy desperately in love with a girl (Pierrot) | fellow travelers who deceived our heroes in the restaurant (the cat Basilio and the fox Alice). In one of the chapters, God's old primer even comes to light, which Papa Carlo gave Pinocchio.An old fairy tale, a spy detective and modern reality - only Max Fry could mix everything in one cocktail!