$re = '/(?s)(?=[^:]*\d[^:]*:)(([0-9]{1,2}h)?[ ]*([0-9]{1,2}min)?:\s*)((?:.(?!(\dh\s\d{1,2}min|\dh|\d{1,2}min)))+)/';
$str = '1h 30min: Title
- Description Line 1
3h: SECOND TITLE
- Description Line 1
- Description Line 2
- Description Line 3
1h 14min: Title
- another Great one 42min: Title - Great Movie
- Description Line 2
- Description Line 3';
preg_match_all($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