What's Nancy Drew doing on Seventh Avenue? In "The Twin Dilemma," to be reissued in March, Nancy -- who, you will recall, can do anything -- fills in for a model who has disappeared just before a benefit fashion show. When the clothes also disappear, Nancy goes in hot pursuit, racing through New York's garment district trying to beat an investigative reporter to the solution of the mystery.

As part of a face-lift program for the Nancy Drew and Hardy Boys books, Pocket Books is bringing the old stories back with new covers just to whet our appetites for a totally '80s Nancy, soon to be out in a new set of mystery tales. Nancy's family and sidekicks are still around, but she's got a new look, described by Pocket Books as "sexy in a low-key way. You're very aware that she's a girl." Her new clothes are "tasteful." The "blue frock" she used to wear has become a scoop-neck tank dress or a mid-length skirt and a soft sweater, with low-heeled pumps and pearl stud earrings. Nancy's car to replace the "roadster?" A brand-new blue Datsun 280ZX.

This totally updated Drew presents herself next August in "Secrets Can Kill" and "Deadly Music," still under the pen name Carolyn Keene. Nancy may now go to rock concerts, but she's still a shamelessly perfect, svelte sleuth determined to get tangled up in every mystery imaginable.