td_nth_child.js

RP.filter_adult = function () {
  // 'this' is the element that received event (checkbox)
  if ($(this).is(':checked')) {
    $('#movies tbody tr').each(function() {
      // 'this' is each element being iterated over
      if (! /^G|PG$/i.test($(this).find('td:nth-child(2)').text())) {
        $(this).hide();
      }
    });
  } else {
    $('#movies tbody tr').show();
  }
}