The One (1970)

Taylor makes a last-ditch effort to find love by becoming a contestant on a reality dating show. Now down to just herself and two other women competing to win the heart of Mason, she begins to feel the artifice of the show fade, and the game becomes terrifyingly real. Amidst the opulent beachfront setting, fairy-tale dates, and ever-flowing champagne, pursuit turns into obsession and rivalry turns into treachery as reality itself blurs.