How is it that an invitation to go to a performance can now lead you to a train station, an abandoned factory or a gas station? Where did the robots appear on the stage and where does the stage itself disappear? Performances last for several days, and the spectator is often forced to act in it himself, and he does it better than professional actors; you are taken through the streets and mansions, asked to dance in the subway, fill out a form and decide for yourself what you just watched. In dance they can stand still, opera can be modern, what is happening? Theater is when classical texts are played on stage to rupture the aorta? Actually, no. This book talks about what is happening with theater from the 60s of the 20th century to the present day: how it has become more interesting and more complex than cinema, what relation it has to modern art and technology, why today it is a space of unprecedented freedom, why all these changes went almost unnoticed. And the most important thing is how to watch it all now.