The thought of Dr. Rossi having an affair was so far from my mind, so far from my comprehension, I have to stop myself from crying out in surprise. She keeps her gaze fixed forward, determined not to look at me. “I was married, of course; it was a reckless, stupid thing that shouldn’t have happened. We were both senior practitioners at the clinc. Megan was smart enough to know the repercussions would be serious, both personally and professionally.”

Dr. Rossi comes to an abrupt stop.

“So she blackmailed you into giving her drugs?”

Dr. Rossi rolls her lips together.

“You have to understand—she could have destroyed everything: my marriage, my relationship with my children, my career, my reputation. My whole life ruined by this one mistake, this one moment of insanity.”

I understand now why she seems so robotic, why she holds herself clenched like a fist; it’s to avoid ever giving in to impulse again.

“She blackmailed me. Made me prescribe the OxyContin.”

“Did she say what she wanted it for?”

Dr. Rossi shakes her head. “She always claimed she had chronic back pain from when she fell down the stairs. It must have got worse over the years, lifting Grace in and out of her chair. I think she developed a dependence.”

“She was an addict?”

Dr. Rossi nods. “She was on it for years. When you called after she was murdered, I was sure Cara somehow knew about it. Megan told me she’d kept the prescription slip as proof of my involvement, to maintain her hold over me. That’s why I agreed to meet you and Cara. I thought somehow you knew.”

We both stare out of the windshield. The silence seems to swell with questions.

“You said Meg was doing an admin role at the practice, so presumably she would have had access to patients’ records?”

Dr. Rossi keeps her face turned away as she replies, “She would have been trained in how to use and update records, yes.”

“So she could have edited a patient’s record?”

“Of course—why do you ask? Do you think she was—” but I cut her off with a shake of my head. She clearly didn’t know about Grace’s real name and age, and there’s no point in telling her now. So Meg would have changed Grace’s details herself. Even though Meg and Grace were well known, the office must hold thousands of patient records, and in the unlikely event someone queried Grace’s it would have been easy for Meg—this wonderful mother—to convince them they were getting confused. I need to keep pressing Dr. Rossi while I still can.

“You said Meg fell down the stairs, but she always claimed Simon pushed her.”

Dr. Rossi turns to me. “I didn’t believe a single thing that came out of that woman’s mouth.”

I don’t want the tension to slacken, for her to find an excuse to stop talking, so I keep asking questions.

“Did Simon know Meg was blackmailing you?”

Dr. Rossi shrugs. “I have no idea. After they left Plymouth he registered under a false name at the office. He made an appointment with me. He wanted to see Grace’s medical records.”