It’s hard to say what will be left to fight over during next year’s Godzilla vs. Kong, since most of the civilized world lies in ruins by the end of Godzilla: King of the Monsters. Or what there is to fight about, for that matter: The premise of these new Godzilla movies is that the giant, radioactive lizard is an ecowarrior, determined to rescue the earth from man’s destructive habits. (While, of course, wrecking everything in sight.)

But what’s that got to do with King Kong? Did he toss a Carl’s Jr. bag into the rainforest on Skull Island?

The 2014 reboot of Godzilla was refreshingly retro and not difficult to follow: Godzilla was the good guy, and the three other towering Titan creatures needed to be defeated. All you needed to know.

But good luck making sense out of King of the Monsters, which increases the Titan hoard to 17 beasties and the principal cast list to a nearly equal number. (One team of useless scientists, including Ziyi Zhang and Bradley Whitford, spends the whole movie watching events on computer screens and making dumb quips while shifting from one remarkably impervious mode of transport to another: stealth jet, submarine, helicopter, etc.)

The main character, other than Godzilla, is Madison (Millie Bobby Brown, from Stranger Things), the teen daughter of scientist Emma (Vera Farmiga), who has invented a device that calms the Titans with the monster equivalent of whale songs. Mom and daughter are soon kidnapped by Tywin Lannister (or whatever bad guy Charles Dance is playing here) — and if you can figure out his agenda, maybe you can figure out what the heck is going on for the rest of the movie.

Other than a lot of destruction, usually at night in the rain. (Skip the 3D glasses.) Washington, D.C., is wrecked, and Boston has the honor of being the site of the final battle. Atlantis also has an underwater cameo — just long enough to look cool before it too is pulverized.

Along the way, respectable actors including Kyle Chandler (as Madison’s Indiana Jones-like dad), Ken Watanabe, Sally Hawkins, David Strathairn, and O’Shea Jackson Jr. all appear and spout overwrought and yet impenetrable lines of dialogue that only muddle the storytelling.

“Storytelling” is, in fact, an overgenerous term, since it implies at least a thread of coherent narrative, which Kind of the Monsters is lacking. The writing is credited to three people, including director Michael Dougherty (Krampus), but it has the air of story-by-committee in which scenes were invented for supposed visual impact then strung together with thin justification.

The CG effects are either cheesy or just hard to see through the endless storm and overediting. (For a taste of how muddy and awful this movie looks, check out the stills on IMDB.com.) Doughtery’s direction doesn’t help matters, since half the time it’s hard to tell where you are, where the characters are, or what’s supposed to be happening.

Godzilla needs a nuclear bomb to recharge? Or maybe he is a nuclear bomb? Or both? But he’s still trying to save the planet? And the other Titans are supposed to help him in his ecological battle (see title) but are instead in thrall to an especially ridiculous three-headed beast leftover from Clash of the Titans? Did the hydra not get the environmental memo?

After the light, comic-book-perky entertainments of 2014’s Godzilla and 2017’s Kong: Skull Island, this installment is a dark, sticky mess that drags on for 130 minutes of ear-splitting boredom and feeling sad for really good actors in a really bad movie.

Maybe Godzilla vs. Kong, with a different director, will revive the fortunes of Warner Bros.’ Monsterverse, but it’s hard to imagine anyone caring.

Grade: F. Rated PG-13. Showing at AMC River Hills, Carolina Cinemark and Regal Biltmore Grande.

(Photos: Warner Bros.)