To be alive is to be in perpetual change: growing, healing, learning, aging. In Shapeshifters, award-winning writer and doctor Gavin Francis considers the transformations in mind and body that continue across the arc of human life.

Some of these changes we have little choice about. We can't avoid puberty, the menopause, or our hair turning grey. Others may be welcome milestones along our path - a much-wanted pregnancy, a cancer cured, or a long-awaited transition to another gender. We may find ourselves turning down dark paths, towards the cruel distortions of anorexia, or the shifting sands of memory loss. New technologies can upgrade us, and even without them our bodies can transform in rare, almost magical, ways - with gigantism, or the sun-sensitivity and facial hair that led porphyria sufferers, once upon a time, to be suspected as werewolves.

Medicine now has unprecedented power to alter our lives, but that power has limitations. As he helps patients face transformations both temporary and sustained, Francis draws on history, art, literature, myth and magic to show how the very essence of being human is change.