That wasn't a fishing trawler. He'd grown up on naval stories from his grandfather, a Ghazi veteran. He knew the difference between a cargo ship's screw and a warship's pump-jet. This was the latter. And it was hunting.
A lone sonar operator aboard a rusting decommissioned submarine must outwit a modern stealth warship after his vessel is mistaken for a ghost from a long-finished war.
Silence. Then: "Confirm. Ghost is a false positive. Stand down."