| Director | Wolfgang Petersen |
|---|---|
| Budget | $160 million |
| Box office | $181 million |
The Poseidon, a luxury cruise ship, is making a transatlantic crossing from London. Former New York City Mayor and firefighter Robert Ramsey is traveling with his daughter Jennifer and her boyfriend Christian Sanders to New York, soon to be engaged. Also on board are former Navy submariner-turned-professional gambler Dylan Johns, architect Richard Nelson, Maggie James with her son Conor, stowaway Elena Morales, her boyfriend and waiter Marco Valentine, singer Gloria, and Captain Michael Bradford.
As most of the passengers are in the ballroom celebrating a New Year's Eve party, officers on the bridge see a huge rogue wave heading towards the ship. To survive the wave, they try to steer the ship to starboard to take the wave head-on, but she does not turn fast enough. The wave swamps and flips the ship completely upside-down, killing the bridge officers along with many passengers and crew. In the ballroom, Robert and some officers rescue Connor on a piano bolted to what is now the ceiling. In the nightclub, Jennifer finds Christian pinned under some fallen lighting equipment and convinces Elena to help them. They, along with gambler "Lucky" Larry, are the only ones to avoid being electrocuted when broken wires electrify the water from the activated sprinkler system. In the ballroom, a badly injured Captain Bradford attempts to restore order and assures the surviving passengers that emergency beacons were launched and rescue is on the way within several hours, persuading them to stay put. Unconvinced, Dylan believes that the only way out is through the bow thrusters, which are now above water. He reluctantly allows Maggie, Connor, Richard, and Robert to come with him, with Valentine guiding them.
In a galley, they encounter a lift shaft, and use a table as a bridge to the other side. However, the table falls out as Richard and Valentine (holding on to Richard's leg) are being pulled up by Dylan. As the damaged elevator car above begins to plummet, Dylan urges Richard to kick Valentine off to save his own life; Valentine falls and is killed below. They eventually reach the nightclub after Jennifer, Elena, and Larry have rescued Christian. They reach the main lobby and use a collapsed elevator as a bridge. As Larry crosses, an engine falls through the floor above and kills him, causing leaking fuel to ignite. Dylan uses a fire hose as a zipline for Jennifer and Robert to cross. Finally, the water pressure due to the ship's prolonged submersion causes the ballroom windows to give way, drowning the occupants, including Captain Bradford and Gloria.
With the ship sinking rapidly, the group escapes through a ventilation shaft and a couple ballast tanks, although Elena hits her head in an underwater passageway and drowns. The survivors make their way to a crew lounge, where they find that the bow section is flooded and impassible, until multiple explosions in the engine room floods the stern, lifting it out of the water. They enter the bow thruster room and are horrified to find the thrusters still running. With their path blocked by the propellers and the control room submerged, Robert goes underwater to stop the engines. He finds the "shut off" switch to be broken, but manages to press the reverse button before drowning.
With the propellers now spinning in the opposite direction, Dylan throws an acetylene tank into it, causing an explosion that destroys one of them, leaving an opening for them to escape. The group jumps overboard and swims to a nearby inflatable raft, just before the ship flips back and sinks stern-first to the bottom of the ocean. After the survivors fire a flare, two helicopters and several ships arrive at the area to rescue them, having tracked the location of the Poseidons GPS beacon.