Cate Blanchett and Rooney Mara were involved in a car accident on the set of 'Carol'.

The actresses were filming a scene where they had to drive a classic Dodge car down an icy road in Cincinnati, but the brakes failed, leaving them in danger.

An on set source said: ''Cate was driving and everything was fine until she tried to stop the car and the brakes failed.

''She kept pumping the pedal as fast as she could, but nothing happened. The girls started screaming at the top of their lungs, speeding past the film crew, who'd pulled to the side of the road after they'd finished shooting.''

Desperate to stop the runaway car Blanchett, 44, pulled the wheel as hard as she could to the right, pulling the car to an angle in the road, but eventually bringing them to a stop.

The source added to National Enquirer magazine: ''It spun around on the icy street but came to a halt as it slammed into a wooden fence. Everyone came running ... as the camera guy started dialling 911, he heard Cate yelling, 'We're OK! We're good! The car isn't good, but we're fine!''

The pair were then said to be relieved when the director told them he had the perfect take of them in the car and they wouldn't have to do the scene again.