In Washington, Special Agent Leroy Jethro Gibbs gets a called from Agent Anthony Dinozzo and is informed that Air Force One has landed in Wichita, KS due to a naval commander dying on board. At the airport, Special Agent Gibbs and Agent Dinozzo meet up with Dr. Donald "Ducky" Mallard and they head down to Wichita. When they arrive on site, Dr. Mallard pretends to be the local medical examiner and Gibbs and Dinozzo pretend to be his assistants. They even used the local coroner to help them with their set up. They were able to fool the FBI and other agents, except Agent Kate Todd, who discovers that they are not only pretending to be the local Medical Examiner; they are there to take over the investigation. They offer to take her aboard and help solve the case. Through much hesitation, Agent Katie Todd agrees to work with them. On their way to Andrews, Ducky discovered that the time of death of the deceased is nearly an hour earlier than what the President's physician has claimed it to be. A little later, Ducky discovers why the time of death between him and the President's physician was different. Being that Commander Trapp had lunch with the President, the President's physician probably rushed to evaluate the President's condition. He did call Trapp's time of death. Once he was sure that the President wasn't in any medical danger, he returned and was gone for nearly an hour. After solving that mystery, Gibbs, Agent Todd and Agent Dinozzo, start bagging the food from the President's lunch. While bagging the evidence, Agent Todd throws up, which makes them question if she has what killed Trapp. At a President's conference, Agent Baer and FBI Agent Fornell have a phone conversation about NCIS having control of the investigation. Agent Baer sticks to their side, even though it's in the hands of a retired cop and ex MP's. Agent Baer informs FBI Agent Fornell that he will have Agent Todd turn the body over to the FBI when she and the NCIS agents land in Andrews. Back on Air Force One, Kate tells Dr. Mallard and Agent Gibbs that she has a stomach virus due to the fact that she slept with Major Kerry who had the same symptoms. After interviewing the staff who were held on board, Agent Dinozzo discovers that the food is very secured but the ribs that were served was flown in from San Antonio and the only person who had ribs was the President. Meanwhile, Agent Todd gets hounded by Agent Baer to turn the body over to FBI when she lands, she tries to get him to see on their point of view but it doesn't work. Agent Todd informs Special Agent Gibbs what she has been ordered to do and that she won't disobey a direct order. Gibbs tells her he understands and they land in Andrews. Agent Dinozzo, Special Agent Gibbs, and Dr. Mallard have taken Trapp's body to NCIS. At a medical lab, Dr. Mallard is examining Trapp's body and Forensics Specialist Abby Sciuto is examining his clothes. Dinozzo goes to Abby and discovers that Trapp might have been poisoned from his own health food. When presenting for Agent Todd, FBI Agent Fornell, Gibbs and Dinozzo about how Trapp died, Dr. Mallard informs them that Trapp suffered a cerebral embolism and had a number of clots that are not unusual to find after suffering from that kind of stroke. Abby tells them that the food Trapp had was free of poison and with that, it's concluded to be a natural death. Now that the case has been solved, Special Agent Gibbs asks Kate if he could join her on the President's flight; she agrees. At a private luncheon, Kate ends her discreet relationship with Major Tim Kerry. After she drives off, Major Kerry suffers the same stroke as Commander Trapp and dies in his car. On Air Force One, while a group of reporters are waiting to interview the President, Agent Kate Todd confesses to Special Agent Gibbs that she ended her relationship with Major Tim Kerry. Later, Agent Dinozzo is called into the crime scene involving Major Kerry; meanwhile, after hours of searching, Abby finally finds something that may have been a cause in Trapp's death. Back on Air Force One, Agent Dinozzo calls Gibbs to inform him about Major Kerry. Also on the line, Dr. Mallard tells them that Major Kerry had multiple cerebral embolisms because he had a bigger dose of what killed him & Trapp. Abby comes on the line and tells them it was venom from an Australian snake. The venom was injected in the suit and it eventually got into the skin. Major Kerry was the intended target and being that he was sick he wasn't on command until the next day, so he didn't wear his suit until then. She also discovers both Kerry's and Trapp's suits were taken to a certain Dry Cleaners. They believe that this is a classic Al Qaida case and with that solved, Mark gives it to the FBI to handle. So, Gibbs gets Todd in a bathroom stall and tells her what happened, but accuses her of killing Kerry being that she was the only one seen with him at the time. After her reaction, Gibbs tells her he was testing her. He tells her what really happened and Todd confesses that Kerry knew Trapp and must have suggested the Dry Cleaners to him. Gibbs comes to the conclusion that the terrorists are after the President and in their own way, were able to get the President to board the plane they are on now. In the back of the plane, a reporter starts to seize and now is when the story starts to unravel. Special Agent Gibbs figures out what their plan has been and stops a reporter from killing the President just in time. After that controversy, Gibbs discovered that Agent Katie Todd has resigned her old job and offers her a job at NCIS, which I'm sure she will take.