After a lengthy wait, the door opened very slowly to reveal a panting old lady wearing a nasal cannula, who’d pulled her oxygen tank to the door with her. Over her shoulder, Strike saw a TV blaring the reality show The Only Way is Essex.

“I’m fine. You just upset me, Arg,” a heavily made-up girl in bright blue was saying onscreen.

Betty Fuller looked as though she’d been subject to heavier gravity than the rest of humankind. Everything about her had sagged and drooped: the corners of her lipless mouth, her papery eyelids, her loose jowls, the tip of her thin nose. It appeared that the flesh had been sucked down out of her upper body into her lower: Betty had almost no bust, but her hips were broad and her poor bare legs were immensely swollen, both ankles thicker than her neck. She wore what looked like a pair of men’s slippers and a dark green knitted dress on which there were several stains. A yellowish scalp was clearly visible through the sparse gray hair slicked back off her face and a hearing aid was prominent in her left ear.

“Who’re you?” she wheezed, looking from Robin to Strike.

“Afternoon, Mrs. Fuller,” said Strike loudly and clearly, “my name’s Cormoran Strike and this is Robin Ellacott.”

He pulled his driver’s license out of his pocket and showed it to her, with his card. She made an impatient gesture, to show she couldn’t read them; her eyes were milky with glaucoma.

“We’re private detectives,” said Strike, voice still raised over the arguing pair on-screen (“At the end of the day, Lucy, she slept, on a one-night stand, wiv a boy—” “Arg—Arg—Arg—this is irrelevant—”).

“We’ve been hired to try and find out what happened to Margot Bamborough. She was a doctor who—”

“’Oo?”

“Dr. Margot Bamborough,” Strike repeated, still more loudly. “She went missing from Clerkenwell in 1974. We heard you—”

“Oh yeah…” said Betty Fuller, who appeared to need to draw breath every few words. “Dr. Bamborough… yeah.”

“Well, we wondered whether we could talk to you about her?”

Betty Fuller stood there for what seemed a very long twenty seconds, thinking this over, while onscreen a young man in a maroon suit said to the over-made-up girl, “I didn’t wanna bring it up but you come over to me—”

Betty Fuller made an impatient gesture, turned and shuffled back inside. Strike and Robin glanced at each other.

“Is it all right to come in, Mrs. Fuller?” asked Strike loudly.

She nodded. Having carefully positioned her oxygen tank, she fell back into her armchair, then tugged the knitted dress in an effort to make it cover her knees. Strike and Robin entered the room and Strike closed the door. Watching the old lady struggle to pull her dress down, Robin had an urge to take a blanket off the unmade bed, and place it decorously over her lap.

Robin had discovered during her research that Betty was eighty-four. The old lady’s physical state shocked her. The small room smelled of BO and urine. A door showed a small toilet leading off the single bedroom. Through the open wardrobe door, Robin saw crumpled clothes which had been thrown there, and two empty wine bottles, half hidden in underwear. There was nothing on the walls except a cat calendar: the month of May showed a pair of ginger kittens peeking out from between pink geranium blossoms.

“Would it be all right to turn this down?” Strike shouted over the TV, where the couple onscreen continued to argue, the woman’s eyelashes as thick as wooly bear caterpillars.

“Turn it… off,” said Betty Fuller. “’S a recording.”

The Essex voices were suddenly extinguished. The two detectives looked around. There were only two choices for seats: the unmade bed and a hard, upright chair, so Robin took the former, Strike the latter. Removing his notebook from his pocket, Strike said,

“We’ve been hired by Dr. Bamborough’s daughter, Mrs. Fuller, to try and find out what happened to her.”

Betty Fuller made a noise like “hurhm,” which sounded disparaging, although Strike thought it might also have been an attempt to clear phlegm out of her throat. She rocked slightly to one side in her chair and pulled ineffectually at the back of her dress. Her swollen lower legs were knotted with varicose veins.

“So, you remember Dr. Bamborough disappearing, do you, Mrs. Fuller?”

“…’es,” she grunted, still breathing heavily. In spite of her incapacity and unpromising manner, Strike had the impression of somebody both more alert than they might appear at first glance, and happier to have company and attention than the unprepossessing exterior might suggest.

“You were living in Skinner Street then, weren’t you?”

She coughed, which seemed to clear her lungs, and in a slightly steadier voice, she said,

“Was there till… last year. Michael Cliffe…’Ouse. Top floor. Couldn’t manage, no more.”

Strike glanced at Robin; he’d expected her to lead the interrogation, assumed Betty would respond better to a woman, but Robin seemed oddly passive, sitting on the bed, her gaze wandering over the small room.

“Were you one of Dr. Bamborough’s patients?” Strike asked Betty.

“Yeah,” wheezed Betty. “I was.”

Robin was thinking, is this where single people end up, people without children to look out for them, without double incomes? In small boxes, living vicariously through reality stars?

Next Christmas, no doubt, she’d run into Matthew, Sarah and their new baby in Masham. She could just imagine Sarah’s proud strut through the streets, pushing a top-of-the-range pushchair, Matthew beside her, and a baby with Sarah’s white-blonde hair peeking over the top of the blankets. Now, when Jenny and Stephen ran into them, there’d be common ground, the shared language of parenthood. Robin decided there and then, sitting on Betty Fuller’s bed, to make sure she didn’t go home next Christmas. She’d offer to work through it, if necessary.

“Did you like Dr. Bamborough?” Strike was asking Betty.

“She were… all right,” said Betty.

“Did you ever meet any of the other doctors at the practice?” asked Strike.

Betty Fuller’s chest rose and fell with her labored breathing. Though it was hard to tell with the nasal cannula in the way, Strike thought he saw a thin smile.

“Yeah,” she said.

“Which ones?”

“Brenner,” she said hoarsely, and coughed again. “Needed an ’ouse call…’mergency… she weren’t available.”

“So Dr. Brenner came out to see you?”

“Hurhm,” said Betty Fuller. “Yeah.”

There were a few small, cheaply framed photographs on the windowsill, Robin noticed. Two of them showed a fat tabby cat, presumably a lamented pet, but there were also a couple showing toddlers, and one of two big-haired teenaged girls, wearing puff-sleeved dresses from the eighties. So you could end up alone, in near squalor, even if you had children? Was it solely money, then, that made the difference? She thought of the ten thousand pounds she’d be receiving into her bank account later that week, which would be reduced immediately by legal bills and council tax. She’d need to be careful not to fritter it away. She really needed to start saving, to start paying into a pension.