Ferdinand Ulrich's Homo Abyssus: The Drama of the Question of Being (Humanum, 2018), originally published in 1961, is one of the most groundbreaking works in Christian metaphysics from the twentieth century. But it is also a difficult book, posing unique challenges to the new reader because of its particular vocabulary, its unusual approach to traditional themes, and the philosophical background that it takes for granted. This Companion is intended to offer readers initial assistance with entering into the text and navigating their way once there. Rather than commenting on the text page by page, it includes five relatively brief essays on basic themes in the original volume and a simplified "digest" of the work's arguments as they appear in each section. It also provides a translation of a paper Ulrich delivered just after publishing Homo Abyssus, in which he presents the essential argument of that work in a more concise scope. A Companion to Homo Abyssus will be indispensable to those who are encountering Ulrich's challenging but profoundly rewarding thought for the first time, and beneficial for those who wish to deepen their understanding of the book's broader implications. Book jacket.