When a ship crosses the equator the crew dress up in wigs and skirts and have fun terrorising the guests.
Various shots of a cruise ship and the crew going about their business. One officer looks through binoculars, we then see him dressed up in a sheet with mud smeared on his face, we see other members of the crew getting dressed up putting on grass skirts make up and wigs. The narrator explains they are preparing for the Crossing the Line ceremony when they cross the equator in midsummer.
They walk around the pool and have fun attacking the guests by using big cardboard scissors and swords, and sawing them in half. Various shots of other guests laughing, a woman struggles as someone tries to cut her feet off. Various shots as people are smeared in gooey stuff and thrown in the pool, the crew jumps in as well. Apparently this ceremony helps to protect against evil spirits.
Note: The ship is the S.S. Pretoria.