Leading man Michel Piccoli plays Pierre, a young musician who briefly catches sight of a beautiful woman dressed in blue and soon spends all of his time trying to track her down. After roaming the streets of Paris in search of the mystery woman, he recruits an old friend to help find her.
Julie Kohler is prevented from suicide by her mother. She leaves the town. She will track down, charm and kill five men who do not know her. What is her goal? What is her purpose?
Marie-Chantal travels by train to her cousin's place to spend a winter holiday, when a stranger - apparently a fugitive from someone aboard - entrusts her with a jewel in the shape of a tiger with ruby eyes. Unknown to her, these false jewels contain a virus powerful enough to destroy all humankind. Doctor Kha is just one among many spies from different nations trying to get their hands on the tiger, or Marie-Chantal... It will give any nation a tremendous control over all others! Marie-Chantal, a snob girl, will evade all attacks by sheer female cunning, and shows tigerish qualities in dealing with her male, and female foes.
A young American art student must decide whether to stay in Paris with her boyfriend or go back to the U.S. when her wealthy father arrives to bring her back.