"zero hour" takes place shortly after the promotion of main character jack o'neill from colonel to brigadier general. with o'neill being the new leader of stargate command (sgc), lt. col. samantha carter has assumed o'neill's old position as leader of the sg-1 unit. the idea to have the episode focus on general o'neill solving various problems at his new job came from the writers' wondering what the general of the sgc does while his teams are on missions.