How do I make a Catch-All Route in Laravel

I need a Laravel routes.php entry that will catch all traffic to a specific example.com/premium-section of the site so that I can prompt people to become members before accessing the premium content.

1. In app/Http/routes.php I create a route that will catch all traffic within domain.com/premium-section/anywhere/they/try/to/go and attempt to find and execute a matching function within PremiumSectionController

2. But there aren't any matching methods, just a catch-all.

   Route::group(['as' => 'premium-section::',
                 'prefix' => 'premium-section',
                 'middleware' => ['web']],
                 function(){
                    Route::any('', 'PremiumSectionController@premiumContentIndex');
                    Route::controller('/', 'PremiumSectionController');
   
                 });
   

.

    namespace App\Http\Controllers;

    use ...

    class PremiumSectionController extends Controller{

        public function premiumContentIndex(){
           return 'no extra parameters';
        }

        //magically gets called by laravel
        public function missingMethod($parameters = array()){
            return $parameters;
        }

    }