Johann Gutenberg built the first printing press in Mainz in the 1450s, and this film follows the attempt to work out exactly how he did it, since no diagrams or working models survived him. Historians and engineers piece together the machine from indirect evidence: surviving pages of the Gutenberg Bible, the metallurgy needed to cast reusable type, and the wine-press design Gutenberg adapted to squeeze ink onto paper under even pressure. The film treats the press less as a single flash of genius than as a combination of existing technologies, papermaking, oil-based ink, and metal casting, brought together by a goldsmith who needed a way to mass-produce something exact. Reconstruction attempts test each part of the process, from cutting individual letter punches to setting a full page of type by hand. The larger claim is about consequences: a machine built to print Bibles ended up breaking the church's monopoly on the written word.