Dark secrets lie in the deep-blue depths of the Mexican cenotes. Underwater caves, connected by a system of natural tunnels. In ancient times used for human sacrifices by the Maya, who saw the cenotes as the gates to the underworld.
But where there's darkness, there's also light. Sun-rays from the surface illuminating the dark for the glimpse of a moment.
The fascination of diving down into this parallel universe can hardly be described.