Safe

Two thieves, Del and Ali, break into a gym on a quiet winters night, searching for a safe. Inside the safe they find only a book; an insane collection of arcane magic and rituals. Before they can leave, Ali reads from the book bringing it to life. It calls out and receives a response. Del and Ali not liking what they have stepped into, try and leave the gym. Its too late, a horde of creatures who are outside have them trapped. They are safe inside though as there is nobody else with them in the gym. They thought.