There are plenty of reasons to love NCIS: The awesome storylines, the action — and guest stars. OK, you got us: Guest stars are one of our favorite things about TV in general, especially when they're A-listers. (The best celeb cameo of all time? Obviously, Brad Pitt, when he played the role of Will Colbert on a Thanksgiving episode of Friends.)
But it's also fun to rewatch a TV series and catch guest stars who were merely starting out in their career, before they became famous. And NCIS had plenty of these guest stars, from kids-at-the-time Abigail Breslin, Zac Efron and Cameron Monaghan to more established TV and film stars like Lily Tomlin, Sterling K. Brown and Taye Diggs. All these NCIS guest stars might make you want to restart the series so you can catch their small roles all over again.
A version of this article was originally published in April 2016.