Christian apologetics is an important area of intellectual endeavour and achievement, standing at the boundaries between theology, philosophy and literature. Yet it has been largely neglected by historians of literature and ideas. In these essays, the author attempts to establish apologetics as a subject deserving of respect in its own right. He analyses the apologetic arguments and strategies of four of the greatest Christian apologists of the twentieth century - Hilaire Belloc, G. K. Chesterton, Dorothy L. Sayers, and C. S. Lewis. He shows how different lines of argument support each other and converge on the same conclusion: that what Chesterton called 'orthodoxy' and Lewis 'mere Christianity' represents the fundamental truth about the relations between human beings, the universe, and God.