Five years after the events of "Jurassic World Dominion," covert operations expert Zora Bennett is contracted to lead a skilled team on a top-secret mission to secure genetic material from the world's three most massive dinosaurs. When Zora's operation intersects with a civilian family whose boating expedition was capsized, they all find themselves stranded on an island where they come face-to-face with a sinister, shocking discovery that's been hidden from the world for decades.
Silvestarska večer na luksuznom brodu pretvori se borbu za opstanak kada brod počne tonuti.
Posejdon, najveći prekooceanski brod, kreće na plovidbu 31. prosina. Nekoliko minuta poslije ponoći, kapetan Harrison (Leslie Nielsen), primjeti jedan od najvećih plimskih valova. To je posljednja slika koju će Harrison zajedno sa putnicima i članovima posade vidjeti u svom životu jer će upravo taj val prevrnuti njihov brod. Tek nekolicinu preživjelih: Mike Rogo (Ernest Borgnine), Linda (Stella Stevens), Acres (Roddy McDowall), Belle (Shelley Winters) i Manny (Jack Albertsonn) Rosen. Predvođeni karizmatičnim svećenikom Frankom Scottom (Gene Hackman) grupica preživjelih i zarobljenih u prevrenulom brodu nastoji pronaći put koji će ih dovesti na slobodu.
Jimmy Dove (Jeff Bridges) radi u bostonskom odjelu pirotehnike, no nakon što se suoči s gubitkom svog partnera, odlučuje napustiti aktivno djelovanje i postati trener novih vojnika. U filmu Odbrojavanje Jimmy sumnja da je iza smrti njegova partnera samo jedan čovjek; Gaerity (Tommy Lee Jones) koji se odlučio osvetiti Doveu. Gaerity postavlja smrtonosne zamke diljem Bostona, postavljajući Dovea na krajnje iskušenje dok pokušava zaustaviti katastrofu.
A cruise ship succumbs to a terrorist act and capsizes on New Year's eve. A rag-tag group of survivors, spearheaded by a priest and a homeland security agent, must journey through the upside down vessel and attempt an escape.
After "The Poseidon Adventure", in which the ship got flipped over by a tidal wave, the ship drifts bottom-up in the sea. While the passengers are still on board waiting to be rescued, two rivaling salvage parties enter the ship on search for money, gold and a small amount of plutonium.