Tl;dr version: volcano go boom, little town go "aaaah!"
The movie gets into the action immediately, opening with a different volcano erupting and a bunch of people getting killed. It gets out of the action almost immediately with thirty minutes of geology mumbo jumbo and Pierce Brosnan and Linda Hamilton uncomfortably trying to bond.
The first act of the movie was structured almost exactly like Jaws. There's a Scary Nature Thing threatening a small, idyllic, American town. Two young people go skinny dipping and suffer gruesome deaths at the hands of the Scary Nature Thing. A Scary Nature Thing expert arrives on scene. A community leader doesn't put the Scary Nature Thing off limits because it could scare off tourists. The community leader and the expert have to go directly towards the Scary Nature Thing to prevent loss of life. That's where the similarities end, although it would have been fucking rad if Linda Hamilton had blown the volcano up with an oxygen tank and a harpoon gun at the end.
This movie is primarily interesting because of the destruction and absolute fucking mayhem caused by the volcanic eruption. There's a really good scene mid way through of the whole town getting blown apart by an earthquake (as we all know, earthquakes work with volcanoes, like remoras and sharks).
While the volcano is wrecking shit, the townspeople realistically freak the fuck out and quickly become more dangerous than the eruption. I feel like they did a good job capturing just how a township would react to such a devastating natural disaster.
After that, it turns into an ad for a fucking Chevy Suburban, as Pierce Brosnan bravely drives the SUV on and off road, through ash and debris, over trees, even through a fucking river.
For best results, turn the sound off and hum the Canyonero jingle while watching that video.
Pierce Brosnan was on his second Bond movie at the time and is charming and likable, as usual. Linda Hamilton was slowly disappearing from the face of the earth and is also likable, even though her character, busy mayor slash coffee shop owner for some reason, was stupid.
Together, they have absolutely no chemistry what so ever. Not only do they have no chemistry, but the "romantic" scenes between them are creepy as fuck. There's one part where he walks her home from the bar and basically starts pestering her to sleep with him. She tries to change the subject being like, maybe we should have a cup of coffee, and he's like, nah. And then volcano stuff happens allowing her to escape, thankfully, but still, ew.
The movie also has way too much emotional shit. The most infamous part being the part where Elizabeth Hoffman sacrifices herself to a lake of acid to save Pierce and Linda and the kids and dies in a tidal wave of children's tears. The pacing of the whole movie is annoying because it's just a really cool thing (like a lake of acid) followed by a really boring thing (like a woman painstakingly saying goodbye to her grandchildren) over and over and over again for two hours.
This movie is worth watching for the destructive wrath of nature, but nothing else. It's also interesting from an historical point of view because the crappy CG lava was, apparently, considered the pinnacle of special effects at the time. Oh, and it was better than Volcano.
Directed by: Roger Donaldson. Written by: Leslie Bohem. Starring: Pierce Brosnan, Linda Hamilton, Elizabeth Hoffman, Jamie Renée Smith, Jeremy Foley, Charles Hallahan.