The new department is to house a concept space known as Project 109, which will open on 11 May and feature an installation created by men's fashion site Hypebeast.
Following this, it will host experiential activities and pop-ups from brands on a monthly rotation.
Project 109 will also stock a range of curated products such as gifts, technology, sunglasses and fragrances.
The revamped menswear space is also hosting a traditional barber, where shoppers will receive a variety of grooming treatments out-of-hours. There is also an in-store eaterie which will serve coffee and juices by day and cocktails, wine and beer by night.
Over the rest of menswear, fashion brands like Y3 and Dockers will engage shoppers with their own retail installations. These will also rotate on a monthly basis.
Designed by Virgile + Partners, the 28,000 sqft department has been nine months in the making, and comes as part of a four-year makeover for the flagship store.
Stacey Cartwright, group CEO, Harvey Nichols, said: "Customers can expect an unrivalled experience in luxury retail … It’s a hugely exciting time for the menswear market and we couldn’t have picked a better time to create the ultimate shopping destination for menswear in London."
The retailer recently held a cocktail masterclass with Grey Goose at its Fifth Floor Bar, which has also been renovated.
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