D&D adventure

You stumble upon a huge castle with peeks at every sight.the the walls have weeds all over, and some of the bricks have fallen off. You believe it will be the not so perfect place place to stay and sleep, but you will because you a cold and hungry. When you get inside, it smells like many things have died in here, then the doors slam behind you. You try to open it but they're locked, you come to a realization you need to find your way out, or even fight out.