Tom Clancy's Rainbow Six: Critical Hour is a 2006 tactical first-person shooter video game developed by Ubisoft Quebec and published by Ubisoft exclusively for the Xbox. It is the fifth game in the Rainbow Six series. The game's plot set during John Clark's retirement as leader of international counterterrorist organization Rainbow recaps several past missions Clark handled during his time commanding Rainbow. Critical Hour primarily consists of remastered levels from Rainbow Six Rainbow Six: Rogue Spear and Rogue Spear Mission Pack: Urban Operations. Fitting with the game's theme gameplay is reminiscent of these titles contrasting with the gameplay changes introduced in Rainbow Six: Lockdown.