https://www.facebook.com/events/627764096970045/

In remote New Zealand, “Harry” and his fellow underwater obsessives set out to dive what could be the deepest-dived cave system in the world. Controversially, they plan to use hydrogen as a breathing gas, adding to the many hazards the team faces. As he prepares to confront the dark waters and life-threatening cold, he questions the costs of his passion.