SINGAPORE - Heroes don't always own chiselled jaws and plucked eyebrows, hurdle tall buildings in a single bound and have names like The Rock. Heroes also come with receding hairlines, creases on their bespectacled faces and swim in the muddy water of caves. Somehow they get through the rock.

Heroes aren't always young and familiar, they're also middle-aged divers with names like Richard Stanton and John Volanthen, an army medic called Dr Pak Loharnshoon and Thai Navy Seals whose names we might never know. Just everyday guys you'd never glance at twice, who quietly go deep into the earth to find, and save, life. In Thailand, they succeeded.