Testa is a gifted linguist recruited into the Allied Cryptanalysis Department during 1951, pulled from his university post by an old mentor. His assignment sounds impossible: decipher encrypted radio transmissions that the enemy has been using for months. The catch is that nobody has ever successfully decoded them because the encrypted signals produce only animal sounds, specifically wolf howls, with no discernible linguistic structure beneath the noise. Convinced that traditional cryptographic methods won't crack this puzzle, Testa pursues an unconventional theory. The transmissions aren't just encrypted. They're being sent by actual werewolves, creatures everyone thought were mythology. His determination to understand this impossible code drives him across dangerous territories in search of a living subject, someone who can help him understand how human intelligence works when channeled through a supernatural lens. When he finally captures Yonaga, a female werewolf, the real work begins. She becomes both his research subject and an unexpected window into a hidden war that few know exists. Their unlikely partnership challenges everything Testa believes about language, monsters, and the nature of intelligence itself.