If you like halibut, you’ll love this …

What happens when the Pacific Ocean unexpectedly turns on humankind (not to mention the occasional sea lion)?

We’re not talking simple typhoons or tsunamis here, amigos. We’re talking a hidden, deadly menace creeping inexorably through the cool waters of the Pacific Northwest, threatening everything in its path with certain death.

That’s the basis of James Powlik’s electrifying “Sea Change,” a solid contender for best submerged supermarket suspense paperback of 2000.

Like all the finest supermarket literature, “Sea Change” (2000, Island Books, Dell Publishing, New York, N.Y., $6.99, 481 pages) has everything – abalone pirates, a ghost ship, dead otters, self-serving environmentalists, dead whales, a self-sacrificing physician and dead sailors.

Did I mention arrogant marine biologists and dead sharks? Gotcha covered, pardner …

Trouble starts when two illegal abalone “harvesters” encounter a foul-smelling, flesh-eating underwater menace lurking in the waters off Vancouver Island, British Columbia, one fateful August evening.

By the time the carefree shellfish scoundrels realize they’re under attack, it’s already too late. Their skin is melting.

The plucky pair gamely fight back by setting fire to themselves and blowing up their boat, but their fate is sealed (particularly after they blow up the boat).

The deadly, unseen entity moves on, eventually claiming the entire crew of a rusty Japanese freighter (except for the first mate, who shoots himself), an Indian boy who goes to the aid of the partially melted abalone thieves, a 6-year-old tourist and dedicated marine mammal researcher Mark “The Junkman” Junckers.

Yeah, it got The Junkman …

The seagoing scourge also takes out womanizing Hollywood entertainment mogul Howard Belkin, the only child of a vaudevillian father and a radio jingle-singing mother who rose from his humble beginnings to create the hit TV series “Bluebirds” about a trio of crime-fighting flight attendants.

(You got all that, right?)

Exit Howard, his girlfriend, his charter boat crew and the partially eaten shark he caught shortly before being killed by the mysterious something that’s rampaging through the waters of the Pacific Northwest.

But exactly what is this amorphous something – a waterborne supervirus, a sentient glob of toxic waste, a 300-foot killer squid with eyes as big as a house or the ocean itself striking back after decades of environmental abuse?

I know what many of you are already thinking: “Hey, it’s a supermarket paperback. That means the underwater menace has to be an old German U-boat full of dead Nazis returned from their watery grave in the Bermuda Triangle to commit unspeakable acts of vengeance.”

Nice try, but no cigar. This is a rather complex supermarket paperback and, let’s face it, reanimated Nazi submarine crews are just a little too commonplace for today’s more sophisticated readers.

No, if you’re going to unlock the mystery of “Sea Change,” you’re going to have to make a quick trip to the supermarket. Feel free to pick up a six-pack and a bag of Chee-tos while you’re at it, but you might want to steer clear of the fish sticks and pickled herring for awhile …

Originally published October 1, 2000