Was it confirmed that an individual went overboard. Some years ago (pre-cameras) when we left Civitavecchia, Italy, right after dinner there was an Oscar, Oscar announcement. Saw crew members scurrying all over the place. We were on the Serenade and were ordered to our cabins so that they could control and inventory of all the passengers. They did this some 3 times. We had a balcony cabin, and it was a sight. Searchlights and other equipment not only from the Serenade but other cruise ships and other vessels that were in the area joined in the search. After some 4 hours of searching approval to leave was given by the Italian Coast Guard.
The good news was that everyone was accounted for, and it was surmised that someone had left either a shirt or jacked on one of the loungers and it blew into the water.
To this day I still don't understand why they did not require all passengers to meet in a location and scan their sea passes rather than a physical inventory while in cabins.