He was relieved
When the voices drifted away until they vanished, he sighed a sigh of relief. His strategy had not yet been wrecked. He still had a chance to locate the book! And, despite his intense concentration, he had no idea how significant the book would prove to be.
The door was locked
He carefully opened the janitor’s closet door and peered inside the corridor. He swiftly got outside and walked toward the third door when he noticed it was empty. As he reached for the doorknob to pull the door open, he saw it wasn’t moving – this door was locked.