A stunt man and woman were suspended 25′ beneath a helicopter. The helicopter pilot flew through the skyscrapers of Chicago at night weaving through the buildings at approximately 60 mph with 10′ of rotor clearance per side. The stunt performers would pendulum up as the helicopter executed its turns, at one point rising to the level of the ship. A helicopter camera ship filmed this by following directly behind the lead ship. The altitude ranged from 600′ to 1500′.