Dante's Peak (1997)

​Plot
Four years after losing his partner Marianne to the sudden eruption of a Colombian volcano, United States Geological Survey volcanologist Dr. Harry Dalton is assigned to investigate seismic activity near the fictional town of Dante's Peak in Washington that borders a dormant stratovolcano. Harry arrives as the town celebrates its founding anniversary, and meets the mayor, Rachel Wando and her children Graham and Lauren.

Rachel offers to take Harry with them as they see her mother-in-law Ruth that lives up the volcano. While there, they find dead wildlife and two dead people boiled to death by a hot springs. Harry fears the heat came from volcanic activity and convinces his superior, Dr. Paul Dreyfus, to bring a team to study it further. They arrive, but after a week, find no evidence of any activity. Harry tries to convince Rachel to prepare the town for a possible disaster, while falling into a budding romance with her.

As Harry and the USGS team prepare to leave, Harry discovers that the local water has become dirty and odorous, and the water supply is contaminated with volcanic residue. Harry confers with the rest of the team, and they agree an eruption is imminent, and they start trying to prepare the town for an orderly evacuation before the eruption. Just as they are organizing the townpeople, the volcano suddenly erupts, sending everyone into a panic and making evacuation difficult. Paul contacts the National Guard for help, while Harry and Rachel go to find her children, who have gone to get Ruth. They arrive just as a lava flow engulfs her cabin, and the five attempt to retreat by crossing a lake on a motorboat. Halfway across, they find the lake has become acidic due to sulfur-rich gases from the volcanic activity, destroying the motor and eating away at the boat. Ruth sacrifices herself to push them to shore, and she later dies from chemical burns. They eventually take a truck from a ranger's station and outrun the lava flow, collecting Ruth's dog Ruffy as they race back to the town.

Meanwhile, the National Guard has arrived and helped with evacuation. The USGS team are the last to leave via a bridge, but as they cross, a lahar caused by melting snow sweeps across it, and Paul is lost to the waters. The others get to a safe vantage point while trying to contact Harry.

Harry, Rachel, and the kids make it back to the empty town, but without the bridge, have no way to escape. Harry checks his team's equipment to find that the volcano is due for a catastrophic explosion. He grabs a distress radiobeacon from their supplies and speeds towards the entrance to an abandoned mine that Graham knows of. They clear the mine's entrance just as the volcano laterally explodes, creating a pyroclastic flow that wipes out the entire town. Outside of town, the USGS team believe Harry to be dead.

Harry, Rachel and the children move deeper into the mine for more protection to wait out the eruption. Harry realizes he forgot the beacon in the truck, but when he tries to go back and get it, a rock fall breaks his arm and traps him in the truck. However, he still manages to activate the beacon.

Some time after the eruption has subsided, the USGS team notices the signal from the beacon, and dispatches search and rescue teams. Harry and the Wandos are freed from the mine and flown out by helicopter. The movie ends showing the obliterated town before turning to the volcano, now reduced to a menacing caldera, bearing an eerie resemblance to Mount St. Helens. Ominous music in the background hints that it will erupt again in the unknown future.