Hollywood beauty Halle Berry had to act out sex scenes alone in new movie PERFECT STRANGER because onscreen lover Bruce Willis couldn't make the shoot. The sexy star was forced to writhe around on a bed while the crew played a tape recording of Willis' voice. Editors later used computer technology to put the pair together - the first time the technique has been used for a sex scene. A set source says, "Halle wasn't phased performing solo. Although she, in effect, keeps her hands to herself, she is very convincing indeed in the love scenes." Willis recently revealed he found himself blinded by Berry's beauty while making the film. He said, "I get all awkward. She's beautiful. It's almost like looking at an eclipse of the sun. "You have to take a pin and poke it through a card and look at her through that. "You could damage your retina."