A spa dome will set off in September to visit seven major city centres across the UK with the aim of delivering over 900 complimentary treatments, over 40,000 complimentary product samples and numerous cases of champagne.
Visitors to the dome will be greeted inside with a glass of chilled champagne and will then be pampered in one of four secluded treatment pods.
All treatments will be complimentary "express" versions of beauty treatments offered at the London spa and administered by The Sanctuary's trained therapists.
One of the treatment pods will offer a complimentary consultation with a scientifically certified skin imaging service, created by Beau Visage.
The service provides the customer with an in-depth analysis into what is happening under the surface of their skin and what to do about it.
In addition to the beauty treatments, visitors will be able to try out The Sanctuary spa's product range and receive a complimentary sample of its Essentials Body Butter.
Emma Keyworth, senior marketing manager at The Sanctuary, said: "Having worked with iD on in-store marketing in my current role and in my previous roles at Revlon and Bourjois over the past eight years, I knew exactly which agency could create a big bang for The Sanctuary's 30th birthday."
PZ Cussons, the maker of Imperial Leather and Carex soap, acquired The Sanctuary from British private equity group HgCapital for £75m in January.
It plans to open more day spas in the UK and overseas, as well as extending the range of Sanctuary-branded health and beauty products.