Mermaids for Love(1968)

Petros, a race car driver and son of a construction mogul, hears about an island with promising business opportunities. He tells his father, they have to buy land there but Flora, a night club owner also learns about it and arrives at the island before him. Their competition disturbs the peaceful lives of the island's residents. Marina, the daughter of the local restaurant owner falls in love with Petros while Flora charms the men of the island and especially Nicolas, causing his fiance's jealousy. She on the other hand falls for Iasonas, the son of the island's Lady who worries about the outcome of these events.

Official site