The Tattered Cover bookstore in Cherry Creek was a beloved gathering place, but the building that housed it was an ugly lump. It wasn't always that way, however. Originally, the structure at 100 Fillmore Street was a swank, modernist landmark housing a branch of the now-defunct Neustseter's department store; in the 1970s, when mid-century modern was out of style, the chic curtain walls were stripped off and replaced by aggregate. But now, in its reincarnation as Pura Vida, a glitzy gym and spa, the building has recaptured its lost glory, clad in a neo-modernist vocabulary of details, including huge wraparound windows on the upper floors. The spa is owned by a partnership including J. Madden, son of big-time developer John Madden. But it was the work of developer the Sturm Realty Group and the good folks at Gensler notably Blake Mourer and Semple Brown Design that turned this sow's ear into the best silk purse in Cherry Creek.