This book contains a concise introduction to one of the most fundamental branches of philosophy, which deals with reality and its nature. It is based on a series of lectures which the author has been giving for several years to first-year undergraduate students as part of their Philosophy of Being, Cognition and Value program at the University of Warsaw. Among the topics discussed are such metaphysical questions as "Are we fundamentally free?," "Does time really pass?," "Are there any abstract objects?," "What is causation?," "What are necessary and possible truths?." The book is aimed at absolute beginners, so it does not presuppose any previous knowledge of philosophy from the reader. However, it is not a dumbed-down "airport fiction" either. The main goal of the book is not only to entertain and inform but to challenge the reader's little grey cells as well. For those who would like to pursue the subject a bit deeper, the book comes equipped with an extended list of further reading.