LONDON — Long a trailblazer in beauty, Harvey Nichols is looking to do the same in wellness , opening a Pilates studio, offering aesthetic and therapeutic beauty services, and serving up functional drinks and a variety of vitamin supplements. The store, which is in the midst of a three-year refurbishment, has torn up its fourth floor and dedicated the entire space to wellness with a 360-degree offer that also includes clothing and accessories. An announcement is expected Thursday. “Well-being has become a core part of how modern luxury is defined by our customers,” said Lucy McPhail, Harvey Nichols ‘ beauty director. She described the new fourth floor both as a “destination and a cohesive space that marks an important step in the continued evolution of our Knightsbridge flagship.” You May Also Like At the heart of the new space is Pilates in the Clouds, a Reformer Pilates studio and the only one in London offering advanced-training “Cadillac” classes, and private full-apparatus sessions.…