The boat left early, cutting clean through the flat blue water north of Cancún. The sun was already working, but the air still carried a softness that would not last. Isla Mujeres sat low on the horizon, quiet and sure of itself. It did not need to announce anything. The water did that. We went out to dive. The first descent was into the Museo Subacuático de Arte (MUSA), though no name quite prepares you for it. You drop beneath the surface and the world changes from wind and