Out of all the stars who have made an appearance on NCIS, Zac Efron is easily one of the most notable faces. However, his role went under the radar for many because it took place all the way back in season three and was before his big breakthrough in High School Musical. Millie Bobby Brown had a similar experience, appearing on the show a couple of years before her rise to stardom on Stranger Things.

Another star who played a role in the show is Tom Hank's eldest son Colin Hanks. He appeared as "Parsons" in three episodes of season eleven. The one and only Jon Cryer even appeared in several episodes as well. Watch the video above to find out what other celebrities starred in NCIS!

These Stars Had Guest Appearances On NCIS

These Stars Had Guest Appearances On 'NCIS'