On August 1, the Pacific Sun ran into a heavy storm 400 miles north of New Zealand, hitting 25-foot-tall waves and 50-knot winds. Its 1732 passengers weren't prepared to endure the madness that ensued. Absolutely crazy.
The video seems like a slapstick comedy until you see people smacking against columns and walls. However, they were lucky: After returning to Auckland from its eight-night trip to the Vanuatu islands, only 42 passengers were injured.
One of the passengers said: "It was like being in a disaster movie. There were screams and people crying as they looked for their lost children." It sounds exactly like a cruise in good weather, but with moving furniture. [The Scuttlefish]
Update: It's not from the same cruise, but I've just found this video showing how the above may have looked from the outside: