Masked assailants crash the president's daughters birthday party in New York City.
Commander Lowe is called off leave to assist in the rescue of Alice Reynolds.
The Alice Reynolds kidnapping and underground carpark siege escalates.
The aftermath of the St. Patrick's Day siege.
The White House is on lock down after 2 unrelated incidents close to the grounds cause suspicion.
Vice President Gavin Lawson learns of the event that is unfolding in the White House.
After threatening Chief of Staff Andrew Whitmore, a personal secret reveals Holt's motivation.