Could this secretive UK project be the key to life beneath the waves?

Deep's ambitious project aims to establish a 'permanent human presence' under the sea from 2027. Picture: Deep/X
Down an easy-to-miss turnoff on the A48 just outside Chepstow on the Welsh border, the gentle rumble of trucks, cranes and people at work mixes with birdsong in what is an otherwise peaceful rural setting.
It is a crisp and sunny winter morning when I visit and, at first glance, the site appears to be little more than prefab containers and a car park. Yet, behind the scenes a group of men and women with expertise in diving, marine biology, technology, finance, construction and manufacturing are building something extraordinary. They have come together with a single mission statement: to make humans aquatic.