Polar Star by Martin Cruz Smith

An American crewman rides the catch over to a Soviet processing vessel (1983).
Photo by Tony Allison.

The story starts off pretty simple: Arkady is working on a Soviet factory ship cleaning fish on the fish disassembly line until they find one of the women crew members dead. Then things start to slowly get more complicated. First we have politics in the form of the Political Officer and his henchmen. Then Soviet Naval Intelligence makes an appearance, and wherever you find them, the CIA can't be far away, and they aren't. And don't forget the Russian mafia, trading central Asian hashish for cocaine. Some aspects of the story are a little far-fetched, but truth is often stranger than fiction, and people are complicated, more so when the situation is constrained, and this one certainly is, so I'm gonna give it a 'plausible'. As always, it's the details about life that make the story, and this one does a good job of it.

Goodreads page: Polar Star by Martin Cruz Smith