PHP Redirect

I was having problems in getting the syntax for a php redirect in my validated booking form.

What I need is a redirect to a response page after the form input fields are verified.
The php redirect.php should do this.

The code:

<?php
header( 'location: BWVH/movie_book.php' ) ;
?>

Which is exactly what is not working here!

Actually it does if it is placed in the php file in the correct place. Again, this is another area in which I still have a lot to learn. I need to look at the difference between the _GET and _POST method for forms and the significance of PHP_SELF.