Jenny nodded, then walked after Azzurra, now at a faster pace. Every few paces, she would turn and look behind her, now paranoid that any drop of vigilance would lead to the two of them being brained by a mysterious flying rock. No coping mechanism she can think of, no tactic found in any psychology book she read, could calm her nerves. "What's going on?" she asked, looking back once again. "What's happening? Why us?"