Bicycle Hidden Playing Card Deck. A deck that is shrouded in mystery, Hidden invokes the symbolism of secretive societies. Let Bicycle playing cards be your guide through the world of mysterious symbols. These playing cards feature designs inspired by societies that use various signs and passwords to safeguard their best-kept secrets. While the deeper investigation by truth seekers has made these symbols more recognizable to most, their secrets remain hidden. Secret Societies - inspired card backs and ace of spades and illustrated custom court cards reflecting the symbols of Freemasonry.