add_filter( 'the_author', 'guest_author_name' ); add_filter( 'get_the_author_display_name', 'guest_author_name' ); function guest_author_name( $name ) { global $post; $author = get_post_meta( $post->ID, 'guest-author', true ); if ( $author ) $name = $author; return $name; }