“Eva,” Ethan said, coming between me and her to shield me. His voice was relaxed, but it also had a strong, authoritative sound that showed he was getting impatient. I told you to go away. Don’t make me have to tell you what to do.”

I got up slowly, feeling my heart beat fast. A mixture of excitement and wariness came over me. It felt to me that whatever would happen between them had been building even before I met them. I remained where I was, paying attention, in case things ...