Season four begins following the departure of Special Agent in Charge Leroy Jethro Gibbs. Gibbs resigned his NCIS position after his repeated warnings about a terrorist attack go unheeded. The final episode of season four shows Gibbs going to his mentor’s house in Mexico.
As the fourth season opens, Tony DiNozzo leads the NCIS investigative team. Gibbs returns to lead the team at the end of the second episode of the season. The season has a number of outstanding episodes that move the show forward and create added depth to various characters. These are the top episodes of the season in no particular order. Warning these reviews will contain spoilers for each episode.
The team is called out to investigate a murder on Halloween. All is not as it seems when the team begins to investigate the murder. The murder is directly connected with the kidnapping of a small girl and soon recovery efforts are underway to find the girl. The girl’s mother acts in suspicious manner and eventually leaves the home with her sister while Ziva is left with protective duty.
The mother is eventually found at her place of work trying to access valuable information for the kidnappers. The final scene shows the mother punching her “sister” after her daughter is found safe. The sister was one of the kidnappers and the mother turns out to be an only child. On an additional note, Halloween shows some surprises for the characters. McGee has a date with an NFL cheerleader and Abby comes dressed in a surprising Halloween costume: Marilyn Monroe.
McGee is met at his front door by his sister, Sarah, who is covered in blood and has no idea how it happened. As events unfold McGee lies to try to solve the case alone and come to the aid of his sister. Eventually McGee is found out and must face Gibbs with his actions. McGee explains himself and Gibbs uncharacteristically accepts his “apology”. The team finds Sarah and works to piece together the events and clear her name. Sarah reveals to the team the secret of McGee’s new fortune, he is a best selling author.
An engineer completes testing a new prototype of an automatic vehicle. When the test is over the car locks the doors and starts the engine to cause carbon monoxide poisoning. The NCIS team investigates the contracting firm and starts to narrow down the suspects. The team finally discovers that one of the engineers was responsible for the reprogramming of the vehicle and the murder. Part of the ongoing story of Tony’s undercover work with Jeanne, daughter of an international arms dealer, leads Ziva to believe that Tony is hiding an illness.
McGee is the central character of another episode where someone is killing individuals who match characters in McGee’s latest book. Each victim matches the description and murder weapon used in the book. McGee is forced to admit that he has used the team as inspiration for the characters in his book, which make all of them targets. McGee eventually discovers the means that the killer used to get information about the book. McGee uses an old typewriter to write his manuscripts and the killer found the typewriter ribbon in the trash to read the book early. The killer is finally caught when he tries to kill Abby and McGee admits his feelings for Abby.