8 Greatest NCIS Guest Stars You Totally Forgot About

Even though it’s not the guest stars who make the show, but the regular cast, there is some magic about one-episode characters played by someone the audience knows and loves. Just like every major procedural on TV that has been running long enough, NCIS had its fair share of actors, hosts and even political figures joining the team.

Here are 8 biggest names who have joined the NCIS family throughout the years, and where exactly in the show you can find them.

Troian Bellisario

Best known for her portrayal of Spencer Hastings in Pretty Little Liars, Bellisario appeared in two episodes of NCIS as Agent McGee's sister, Sarah. Her appearance on the show before her big break is easy to explain, as Troian is the daughter of Donald P. Bellisario, the mastermind behind both JAG and NCIS.

Zac Efron

Zac Efron's appearance on NCIS came in the same year that he became a living legend to thousands of teenage girls thanks to the success of High School Musical. The show was lucky enough to have him drop by for Season 3 to play Danny, one of the boys who got their hands on Commander Wilkerson's cell phone.

Just weeks later, the actor became a huge Disney star and had to give up small roles in network dramas and procedurals.

Jamie Lee Curtis

Not only did the actress stop by to film an episode, but her character, Dr. Samantha Ryan, had a full five-episode arc during the show's 9th season. She portrayed a potential romantic interest for Special Agent Gibbs and expressed interest in returning to the iconic show if there was a chance to develop a storyline, but unfortunately that chance never came.

Misha Collins

Before landing a life-changing role on Supernatural and stealing the hearts of many viewers as the angel Castiel, Collins was making the rounds on television. He had small roles on NYPD Blue, CSI, ER, Monk, and then, of course, NCIS.

In an episode called Singled Out, the actor portrayed Justin, a man who accidentally steals a car with a woman in the trunk.

Glen Powell

Actively gaining fame now and securing the roles in Hollywood blockbusters, the actor didn’t have as much of a recognition back in 2012, when he appeared in two episodes of NCIS. His role wasn’t in any way comedic, as he portrayed Evan Westcott, the brother of a veteran struggling with PTSD.

Millie Bobby Brown

Many people still haven't gotten over the shock of discovering that their favorite Netflix star had a moment of fame on Grey's Anatomy, but the truth is, the actress has been working long before the success of Stranger Things.

In the NCIS episode Parental Guidance Suggested, Millie portrayed Rachel Barnes, a sweet little girl who turned out to have murdered her own mother in favor of her father.

Bob Newhart

The title of guest star with the most heartbreaking story goes to Bob Newhart, who briefly portrayed Dr. Walter Magnus, the former NCIS chief medical examiner. He was replaced by the fan-favorite character Ducky, portrayed by Donald Mallard, as it was discovered that he suffered from Alzheimers.

Michelle Obama

If there is a way to beat this one guest star, we have yet to see it. When she appeared on NCIS during its 13th season, Michelle Obama was still the First Lady and had a reason to appear on a scripted drama.

Playing herself, Obama stopped by to spread the word about her organization that supports veterans, active military and their families. And it was a truly ingenious PR move that has yet to be surpassed.