The universe begins, in this film's account, about 14 billion years ago as a point of near-infinite density that expands outward in a single explosive event, and the documentary follows that idea from its first proposal to where cosmology stands today. Physicists and cosmologists appear in interview, laying out competing ways of describing what happened in the first instants after the Big Bang and how galaxies, stars, and eventually life condensed out of the resulting expansion. The film pairs this with a score by Brian Eno, using music rather than narration to carry long stretches of cosmic imagery, from swirling nebulae to the large-scale structure of galaxy clusters. It stays close to mainstream physical cosmology rather than surveying rival theories in depth, treating the expanding, aging universe as settled ground and spending its time instead on how scientists arrived at that picture and what still sits at the edges of it.