Eighteen months after Day 1's foiled assassination plot, Day 2 finds Counter Terrorist Unit agent Jack Bauer (Kiefer Sutherland) officially stepping into the role of America's protector as he attempts to stop terrorists from setting off a bomb in Los Angeles. During his hunt for the nuclear device, Jack becomes romantically involved with Kate Warner (Sarah Wynter), who suspects her sister's fianc~ is working with Middle Eastern terrorists. Behind-the-scenes political intrigue centers on David Palmer (Dennis Haysbert), now president of the United States after surviving Day 1's assassination attempts. While Palmer supports Jack and CTU's efforts to track down the nuclear device, Vice President Jim Prescott (Alan Dale) and Palmer's own Cabinet question the president's decision-making ability and seek to undermine his authority at every turn. Meanwhile, Jack's daughter, Kim (Elisha Cuthbert), who was rescued from kidnappers in the first season, turns the tables during Day 2. This time, it's Kim who does the kidnapping---or, as she sees it, rescuing---of a child she's been babysitting in order to protect the girl from an abusive father. Later in the day, guest star Kevin Dillon appears as survivalist Lonnie McRae, who takes Kim hostage after convincing her that the nuclear bomb has already been detonated in L.A. Familiar faces returning to action include CTU agents Tony Almeida (Carlos Bernard) and Michelle Dessler (Reiko Aylesworth), whose relationship begins to develop romantically under the day's stress; CTU director George Mason (Xander Berkeley), who is exposed to radiation during a fierce gun battle; and First Lady Sherry Palmer (Penny Johnson Jerald), who reveals a dark side in her manipulations of the president for political gain.

Enter a world of dynastic power struggles and family treachery. This intimate landmark series narrated by David Attenborough immerses us in the lives of five of the most celebrated and endangered animal families. Witness their incredible determination to protect their family line in the face of challenges to their leadership or from the often harsh environment around them.