The Mystery of the Fifteen Sounds

1938. A boy named Roger Brown dreams of following his explorer father into the wilds of Borneo. Instead, he gets a laboratory. His cousin Grover runs a scientific research facility packed with the most advanced equipment of the era, and when Roger arrives to spend the summer helping out, he finds more adventure than any jungle could offer. Someone has stolen cages of rats infected with deadly pathogens. A spectral phantom kangaroo and its ape-like companion haunt the grounds at night. And through it all echoes the Voice of Doom, a hollow summons that reverberates through the corridors in the dead of hours. Roger must combine his pioneering spirit with scientific reasoning to unravel fifteen mysterious sounds before something terrible escapes into the world. It's a pulp-era children's adventure that captures the breathless excitement of science and exploration at a time when the future seemed both terrifying and magnificent.