Land, sea, air, and space have long been recognized as domains of warfare, and this film argues that cyberspace now belongs beside them as the fifth. It tracks how militaries, intelligence agencies, and private contractors are building offensive and defensive capabilities for a battlefield with no fixed geography, where a strike can disable a power grid, a bank, or a weapons system without a shot fired. Interviews with security analysts and former officials lay out real incidents, from state-sponsored malware attacks on infrastructure to the murkier world of attribution, where nations rarely admit responsibility for what their hackers have done. The film examines the Stuxnet worm's sabotage of Iranian nuclear centrifuges as a case study in what cyberweapons can achieve outside conventional combat, and considers how unevenly international law has kept pace with the tactics already in use. The picture that emerges is of militaries treating code as ordnance, and of a conflict already underway that most of the public never sees.