This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book begins by revisiting some of the founding tenets of critical theory in the context of the establishment of the Institute for Social Research in the early twentieth century. After charting the history of melancholy, it focuses on the work of Walter Benjamin, whose varied engagements with the subject of melancholia prove to be far more mobile and complex than traditional accounts. The book looks at how an affective politics underpins critical theory's engagement with the world of objects. It explores the affective politics of hope. The book outlines the upsurge in theoretical writing on objects/things, especially within the much-touted field of 'object-oriented ontology' (OOO) or 'speculative realism' (SR).