This is not at all what it appears to be! The first two chapters are, indeed, about the swimmers who regular use an underground pool. When a crack appears in the floor of the pool, we are privy to all their reactions. The crack is a metaphor for an unexpected change in our lives, and how everyone responds differently: ‘…many of us remain anxious. Because the truth is, we don’t know what it is. Or what it means. Or if it has any meaning at all’.

One of the regulars at the pool is Alice, who (we learn later) has a rare form of dementia. The second part of the book follows Alice’s declining health. These chapters are terrifying, in the true sense of the word. It is beautifully written, and heartbreaking.

To call this book a novel is misleading. It contains two short novellas, loosely related. If you are looking for a feel-good read about swimmers, I would only read the first two chapters. I found the rest of the book harrowing and frightening, and find it difficult to recommend.