Operation Romantic Cruise
Operation Romantic Cruise was a part of Jadeite's plan to gather energy from humans, which was featured in episode 12 of the Sailor Moon anime. Usagi and Naru wanted to go on the cruise, and upon finding a contest in the shopping district with tickets as a prize, Usagi tried repeatedly to win but only failed every time. Rei found out and used her powers to win tickets, and, claiming to be uninterested, still invited Ami to come with her. Frustrated, Usagi used the Disguise Pen to sneak on board the ship with Luna.
The Youma Thetis attacked the passengers on the ship, stealing the energy of people in love. Ami and Rei were not in love and were thus unaffected, but could not fight back without revealing their identities as Sailor Senshi. Sailor Moon arrived, however, allowing her friends to also transform and battle the Youma. Once Thetis was destroyed, the luxurious cruise ship was revealed to be merely a rusting derelict, and the cruise was over.