$obj1={ _proto=>$base_obj, do_something=>sub{ print $_[0]->get('string')}, string=>'object one'}; $obj2={ _proto=>$obj1, change=>sub{ $_[0]->set('string',$_[1])}}; $obj2->call('do_something'); $obj2->call('set','object two'); $obj2->call('do_something'); $obj1->call('do_something'); __END__ would print: object one object two object one