The pair encounter a couple broken down on the side of the road, shortly before the San Andreas Fault, which has torn a large fissure through the highway and extends for the perceivable length of the fault in either direction. Amid the chaos of looting, Ray steals a truck to continue the journey. Ray and Emma attempt to reach San Francisco in Ray's helicopter until it suffers a gearbox failure, forcing them to make an emergency landing at a shopping mall in Bakersfield. Ben Taylor, a British engineer seeking employment at Daniel's firm, and his younger brother Ollie rescue Blake and they reach Chinatown, successfully calling her parents for help. Panicking, Daniel leaves Blake in an act of cowardice. Rubble from the collapsing parking garage pins her in Daniel's car. Meanwhile, their daughter Blake has been visiting San Francisco with Emma's new boyfriend Daniel when an earthquake strikes the city.
When a 9.1 magnitude earthquake devastates Los Angeles and San Francisco, Ray Gaines, a Los Angeles Fire Department helicopter-rescue pilot going through a divorce from his wife Emma, finds himself rescuing her from a skyscraper in Los Angeles. He begins racing to warn the population of California along with his students Alexi and Phoebe and reporter Serena Johnson.
Hayes discovers that the entire San Andreas Fault is shifting and will soon cause a series of major earthquakes, potentially destroying cities along the fault line. Kim Park are at Hoover Dam testing a new earthquake prediction model when a nearby and previously unknown fault ruptures, triggering a 7.1 magnitude earthquake that collapses the dam Park sacrifices himself to save a young girl.