<a id="hidden_link" onclick="ono('hidden_link','hidden_content','after_process_link')" style="cursor:pointer">Ссылка1</a>

<div id="hidden_content" style="display: none">Текст</div>
<a href="#" id="after_process_link" style="display:none">Ссылка2</a>
<script>
function ono(id1,id2,id3) {
var el1 = document.getElementById(id1);
el1.style.display = 'none';
var el2 = document.getElementById(id2);
el2.style.display = 'block';
handler = function() {
    el2.style.display = 'none';
    el1.style.display = '';
    document.getElementById(id3).style.display='inline';
}
setTimeout(handler,15000);
}
</script>