$re = '/(?<show>[\w ]+) - (?<episode>S[0-9]{2}E[0-9]{2}E?[0-9]{0,2}) - (?<title>[\w -]+)(?: - )(?<res>(?:720p)|(?:1080p))/m';
$str = 'Show Name - S01E02 - This Is a High-Def Episode Title - 720p
Show Name - S01E03 - This Is a High-Def Episode Title - 1080p
Show Name - S01E04 - This Is a Standard-Def Episode Title
Show Name - S01E05E06 - This Is a High-Def Double Episode Title - 720p';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php