有史以来最严重的大地震撼动了南加州。不只把洛杉矶夷为平地,更让住在当地的所有人的生活为之天翻地覆。在整座城市试着在恐怖的地震再度来袭前重新恢复正常时,陌生人也必须担任起英雄的角色。Construction Engineer Stuart Graff is estranged from his jealously possessive wife, Remy, and has an affair with Denise Marshall, the widow of a co-worker. Meanwhile, Remy tries to persuade her father, Sam Royce, who is Stuart's employer, to use his influence to stop Stuart from seeing Denise. Rogue policeman Lew Slade is suspended from the L.A.P.D. for having punched an obtuse officer from another jurisdiction. Embittered, Slade contemplates quitting the police force. Jody, a perverted grocery store manager, lusts after Rosa Amici, sister of Sal, the assistant to Miles Quade, an aspiring daredevil motor cyclist. The lives of all these people are devastated when a major earthquake rips through Los Angeles and reduces the city to ruins.