Five college students decided to take a science course together. The professor's family had a history of craziness and they have been performing scientific experiments in an ancient buried castle for decades. The students did not realize that the castle was buried right under their dormitory. One of the students noticed that an iron plate covering a hole just outside their dorm had been removed, leaving the hole exposed. He peeked in but dared not to enter without some companionship. Five students decided to explore the hole.
In the first part of the Inside World (Registered Version), we travel through the first floor of the ancient castle ruins.