Hook into template redirect before it can redirect

gistfile1.aw

<?php

add_action('template_redirect', function() {
    $tmp = explode( '/', $_SERVER['REQUEST_URI'] );
    $my_slug = 'feeds';

    if ( isset( $tmp ) && $tmp[1] == $my_slug ) {
        load_template( '/path/to/my/template/' );
        // or do what ever you want
        exit();
    }

}, 6);