Question: who are the guest stars on ncis?
Answer: Abigail Breslin.
Lily Tomlin. ... 
Terry O'Quinn. ... 
Lindsay Wagner. This is one of the few geeky castings that NCIS has indulged in. ... 
Zac Efron. Back in Season 3, the CBS drama enlisted the help of Zac Efron in an episode called "Deception." It was a small role, but it gave Zac Efron the chance to shine before he was famous. ...