SickSquirrelTwo on "Site is missing"

I went to check a plugin on a site I'm building. I haven't been there for a week or more. The homepage is blank. The WordPress login is blank, EVERYTHING is blank.

But, I FTP in and ALL files are there.

Index.php is `<?php
/**
* Front to the WordPress application. This file doesn't do anything, but loads
* wp-blog-header.php which does and tells WordPress to load the theme.
*
* @package WordPress
*/

/**
* Tells WordPress to load the WordPress theme and output it.
*
* @var bool
*/
define('WP_USE_THEMES', true);

/** Loads the WordPress Environment and Template */
require('./wp-blog-header.php');
`
Looks ok. Theme directory has 4 themes. So ... why'd my site disappear??