Physicist Brian Greene hosts this four-part series built from his book of the same name, walking through the strangest claims in modern physics with animation standing in for equations. "What Is Space?" asks whether the empty-seeming vacuum is actually a physical substance, using the Higgs field and Einstein's own struggles as evidence. "The Illusion of Time" takes apart the common-sense idea that time flows in one direction, leaning on entropy and relativity to argue that past and future may be far less fixed than they feel. "Quantum Leap" sits with the genuine weirdness of the subatomic world, particles that behave like waves until observed and seem to affect each other across distance instantly. The closing episode, "Universe or Multiverse?", lays out the case from string theory and inflation for countless other universes beyond our own. Greene talks to working physicists throughout, and the series keeps returning to demonstrations and animated models to make each idea visualizable rather than just asserted.