Lurex conjures up visions of slinky lamé dresses fit for an evening at Studio 54, but the reflective threads also tend to pop up around the holidays as an alternative to the ubiquitous sequin. This season, designers are embracing the gleam, showing head-to-toe Lurex looks or pairing metallic knits with shiny silk. At Prabal Gurung, a whimsical printed sweater shot through with shimmery electric-blue fibers was layered over flared silk trousers. Over at Tibi, a boxy knit was paired with a matching cropped sweater and a simple black turtleneck. And at Marc Jacobs, the look was more is more — a black lurex skirt was thrown over silver trousers and topped off with a metallic purple coat.