Are you sure you actually have all the 3 keys? there are 2 level one keys, you only get the level 3 key in samuals lair!
I tried walking around inside a wall too and I am sure that many or most have had this experience. Make the best of it ha ha atlest you have the opportunity to scout the area before you move along <img src="/ubbthreads/images/graemlins/winkwink.gif" alt="" />
