 One dark night, in the deserted streets of Nice... An American car slowly drives past Victor Menda, then slowly pulls up... A come on from the mysterious blonde at the wheel and Victor finds himself kissing her and making love with the gorgeous creature... But as soon as the embrace is over the mantis-like beauty rejects him and, under the threat of a gun, makes him leave the car... Worse, she tries - and nearly manages - to kill him by running over him. Now, cars have plates and Victor traces the address of the monstrous nymphomaniac rather easily. To his amazement he discovers that in the beautiful villa - in front of which the American car is parked - TWO blonde sisters live together, both of whom looking sweet and harmless...