The crew get a day off to explore St. Lucia on board a catamaran which takes them on a deep-sea adventure to see the Pitons up close and personal. Things get steamy between Alissa and Ross at the mud baths while Katie is left out in the cold. The crew welcome a new deck/stew, and Katie pushes Ross to move into her cabin instead of the newcomer. On the crew night out, a surprise guest shows up to dinner, shocking everyone.