Command and Conquer: Generals – Zero Hour is the expansion pack for the 2003 video game Command & Conquer: Generals. Zero Hour added several new abilities and units to each side, and a new mode of play called Generals' Challenge.
Zero Hour also contains 3 new campaigns of five missions each, one for each side, with their chronological order being USA first, GLA second, and China last. Unlike the previous campaigns, which were noted by Command and Conquer fans for not having full motion video cinematic sequences during mission briefing, the Zero Hour campaigns return to that Command and Conquer tradition, each showing a live-action video of a news reporter of the respective side giving details about the situation behind the current mission. The plot behind the Zero Hour campaigns picks up where it left off at the end of the previous campaigns.