Shelley first became famous in the 1970s as THE Charlie Girl. In 1976, she was hand-picked to represent the Revlon Charlie brand, as she was the embodiment the brand's ideal – gorgeous, sexy and young. Makeup artist Rick Gillette recalls, "Shelley Hack was really the perfect girl for Charlie. I remember when Revlon creative director David Leddick had Steen Svensson shoot the first presentation with her that got her the contract." They shot a commercial with her and when it debuted, it was an immediate and immense hit. By 1977, Charlie became the #1 fragrance in the world (the first American-made international bestseller) and Revlon sales figures passed the $1 billion mark. Shelley THE Charlie Girl had catapulted to icon.
Shelley was THE quintessential Charlie Girl and appeared in many, many ads for the brand. In 1977, she appeared in a newspaper ad for Charlie promoting "Charlie's Put-Ons." It was a promo that offered customers a chance to purchase a $20.00 worth Charlie T-Shirt and Scarf combo for only $6.00 with any purchase from the Charlie collection. The T-shirt was blue and came in sizes S-M-L. And the long scarf was blue, yellow and white striped. Of course, Shelley looked fab in both of them.