CTU and Jack Bauer race to get to Abu Fayed before he can detonate a nuclear device in Los Angeles. Tensions rise as one member of CTU doesn't want to work with Hamri al-Assad. Meanwhile, President Wayne Palmer's sister Sandra is promising to bring up trouble while Wayne deals with the toughest hour of his presidency, and Jack is forced to make a heart-wrenching decision. The nuclear device detonates, and evidence comes in that four more such weapons are in the U.S.