Here’s an interesting Italian/German co-production, full of subjects from 1968 protest, recalling the two infamous \*bikini thrillers\*,\*Interrabang\* and \*Top sensation\*, in which three young beauties (Rosemarie Dexter, Doris Kunstmann and Laura Troschel), alluring their male friend (Bernard De Vries), embark on a journey in a luxury yacht around the coast of Yugoslavia, plenty of bedhopping, nudity and the usual hijinks occur before things take a sinister turn when they decide to lock themselves in a cabin and dose up on LSD
IMDB: http://www.imdb.com/title/tt0062249