Margo Harshman plays the role of Delilah Fielding in the NCIS series. She was introduced in season 11 of the series, which is one of the longest-running shows on CBS with 22 seasons on air. The show has a blend of drama, crime, and military investigations. It premiered on September 23, 2003, and its latest season was released last year in October.
NCIS (Naval Crime Investigative Services) was created by Donald P. Bellisario and Don McGill as a spin-off of CBS's show JAG. The storyline revolves around a team of special agents who deal with crimes such as murder, terrorism, and espionage involving the US Navy and Marine Corps.
About Margo Harshman's role in the NCIS
Margo Harshman is introduced in the show in the premiere episode, Whiskey Tango Foxtrot of season 11. Harshman's character, Delilah Fielding, is an intelligence analyst for the Department of Defence, who is responsible for processing and interpreting sensitive information to support national security efforts.
The premiere episode begins with the aftermath of the bomb blast at a military event, leaving the NCIS team on high alert. Delilah, as an analyst, helps the team uncover the culprit with her technical expertise. She helps decipher the cyber communication linked to the attack, which successfully leads to the identification of the terror group, Brotherhood of Doubt, involved in the blast.

Her character arc in this episode is limited, with a subtle romantic relationship developing between her and Special Agent Timothy McGee. Also, her expertise and aid make her a recurring character on the show.
In episode 5 of the same season, Delilah's relationship with McGee is revealed to the team. In episode 9 she assists the team in a high-security breach incident at the Pentagon, the headquarters of the United States Department of Defense. Delilah identified the bug that was responsible for the reach, earning praise from team leader Leroy Jethro Gibbs.
However, her character takes a significant turn in the series in episode 13, where she goes through a life-altering incident. In this episode, the NCIS team is investigating a bombing incident that occurred at the Conrad Gala Hotel and is linked to the terrorist Benham Parsa.

Delilah, unknowingly attends an event at the Conrad Gala Hotel, on the same night when the bomb blast took place. The blast was severe and injured many people, also leading to the death of a few. Delilah suffers a spine injury that renders her permanently paralyzed from the waist down. The episode ends with her coming to terms with the reality and coping with her condition.
In episode 11, the investigation continues, with Delilah returning to work in a wheelchair. She is determined to track Parsa's cyber activity and help the team. She interprets the messages among Parsa's associates and helps in identifying his location in Pakistan. The episode shows her struggle with the new adjustment but also highlights her resilience.
Delilah and McGee marry in season 14 of the NCIS.
Margo Harshman's work beyond NCIS
Margo Harshman is known for her role as Tawny Dean (2000-2003) in Even Stevens and for playing Alex Jensen in The Big Bang Theory (2012-2013). She also played Lisa in Betas (2013-2014). Margo has also appeared in House (2005) and Modern Family (2013).
She has appeared in several movies, including Sorority Row (2009), Fired Up (2009), Keith (2008), and The Even Stevens Movie (2003).