Judith’s hand idly went to the key she kept on a chain around her neck, and her thoughts began to drift into the past, into a much darker time. She shot up from her chair. This wouldn’t do, she told herself. Wouldn’t do at all. There was always something else she could do to keep herself busy. She needed a change of scene, that was all, and she had the perfect solution.

Judith began to take off her clothes. With each garment she removed, she felt more and more released from the stifling constraints of the day. By the time she was naked, she was buzzing with an impish delight. She crossed the hallway, past the Blüthner grand piano she only ever played when she was really very drunk, and took up a dark grey woollen cape she kept by the front door.

Judith’s cape was her most treasured possession. She’d tell anyone who asked, and many did, that it kept her warm in winter, served as a picnic blanket in the summer, and she could pull it over her head if ever she was caught in a spring shower.

Best of all, Judith believed it was a cloak of invisibility. Every evening, come rain or shine, she’d take off her clothes, wrap the cape around herself and step out of her house feeling a delicious frisson of naughtiness. She would plunge her feet into a pair of ancient wellies and stride through the knee-high grass – swish, swish, swish! – to her boathouse. Like the rest of Judith’s house, it was pink-bricked, timber-framed, and somewhat crumbling.

Judith entered the cobwebby darkness and kicked off her wellies. She hung her cape on an old hook, and, still hidden from the outside world by a pair of ancient boathouse doors, stepped down the stone slipway and into the Thames.

It was almost a religious experience for her, accepting the cold water onto her skin, and she exhaled with a whoosh as she leant forward into the embrace of the river. Suddenly she was weightless, supported by the soft water that felt like silk to her body.

She swam upstream, the evening sunshine flashing diamonds on the water all around. Judith smiled to herself. She always smiled to herself when she was out swimming. She couldn’t help it. After all, there might be dog walkers on the Thames Path, and there were very definitely plenty of people in the near distance as she looked at the spire of Marlow church and the span of the Victorian suspension bridge that linked the town to the neighbouring village of Bisham. None of these people were aware that there was a seventy-seven-year-old woman swimming nearby entirely in the nude.

It was just as Judith was thinking, This is the life, that she heard a shout.