In this gripping action-adventure novel, Murray Leinster turns away from the interplanetary settings that typically form the backdrop of his fiction and instead delves into one of the most mysterious places on Earth: the darkest depths of the sea. Expert radar operator Terry Holt is summoned to an unusual top-secret assignment off the coast of the Philippines. What could be responsible for the strange clues that have been surfacing there?
- National Poetry Month
- Mine a Good Book
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- 2025 Libby Book Award Winners and Runners Up
- How Does Your Garden Grow?
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- National Poetry Month
- Mine a Good Book
- 250th Anniversary of the American Revolution
- Earth Day Reads
- 2025 Libby Book Award Winners and Runners Up
- How Does Your Garden Grow?
- Always Available Audiobooks
- Great reads without the wait!
- Everyone Reads: Spanish Titles for Young Readers
- Adapted for Young Readers
- See all audiobooks collections