Mr. Baillie applauds the way the store has brought the project to life. “I’ve never seen something done with this sort of depth, and anyone who comes in can get hooked and spoken to in their own language,” he said, pointing to the art and science collaborations in the Ultra-Lounge and the list of cooking demonstrations to be held over the next few weeks.

But in a commercial world where innovation and change is king — can this notion of sustainability celebrated in a store last beyond the initial effort? Or will it be washed away by the next new wave? The Zoological Society of London and Selfridges have also established a long-term joint project: a 50-hectare, or 124-acre, marine protection area in the Philippines, aiming to safeguard fish species and their coral reef ecosystem.

Awareness about the threat to coral is one of the themes running through the store, with 22 species of live coral breathing and floating in the display area in the Ultra-lounge and spiky pieces confiscated from illegal suppliers as part of the fashion exhibition.

“Washed Up,” curated by Judith Clark, gives a surreal edge to clothes that are far more interesting than mere dresses patterned with fish or jolly sailor outfits.

Ms. Clark, more familiar with museum spaces than a bustling store, has created a marine corner of driftwood and coral, displaying a figure in a historic Victorian bathing outfit in fresh blue and white stripes looking at water-inspired creations from Hussein Chalayan’s bubble dress to pieces from the final Plato’s Atlantis collection from Alexander McQueen. Her own design is a Swarovski crystal-encrusted swimming cap.