This is a book about skin. The strange wonderfulness of our bodily covering. What happens to it when something goes wrong. How the world responds to imperfection and difference. It's about how skin makes us who we are.

Skin serves as a barrier between us and the germs that would otherwise invade and destroy us. It regulates our temperature. Skin remains waterproof even while our entire epidermis replaces itself each month. The body's biggest organ even has its own sub-set of organs - sweat glands, sebaceous glands and hair follicles.

Primeval, sometimes mysterious, forces drive skin-to-skin contact, but erotic desire is but one of many deep-seated urges that make us want to touch the skin of another. Touch is how we express love and affection as well as darker, violent emotions.

Skin keeps the outside out and the inside in. You will intuitively compile information and judgements about a stranger based on their skin and the clothing that covers it. Skin shouldn't give you the measure of a person, but we function as if it does.

Skin Deep explores beauty, ageing, imperfection, health and illness, all of which are closely related to skin, and interrogates whiteness, both historically, structurally and through current notions of white fragility and victimhood. Paradoxically, skin is a barrier and a point of contact. It is miraculous, our biggest organ. It heals itself! It's wafer-thin! Skin cells remake themselves!

Phillipa McGuinness has interviewed plastic surgeons, dermatologists, burn survivors, beauticians, melanoma sufferers, people who suffer from body dysmorphias, victims and perpetrators of racism and all kinds of people who are and are not comfortable in their own skin to write a book where science meets art and culture, history and politics. Philosophy, too, given skin is the point where our self, and our self-perception, struggles with or embraces the way others see us and the way we see ourselves.