Fellow NCIS stars from the past and present are mourning the loss of David McCallum.
David played Chief Medical Examiner Donald “Ducky” Mallard for two decades.
But on Monday morning, the news came out that David died at 90.
His cause of death was reportedly natural causes, but the loss has hit the show and its fans hard.
CBS used an In Memorium card to share the news during the NCIS Day episodes on Monday night.
When NCIS Season 21 begins, the writers will address what has happened to Ducky.
Mark Harmon reacts to David’s passing
“David lived a great, full, long life. I was in awe when I first met him and all of us on the show were honored to have toed a mark opposite him. My condolences go out to Katherine and his family,” Mark Harmon said in a statement to Deadline.
Mark played team leader Leroy Jethro Gibbs on the NCIS cast and worked closely with David for many years.
Brian Dietzen mourns the passing of his friend
The NCIS cast member who worked the most with David was Brian Dietzen. He still stars on the show as Dr. Jimmy Palmer, and Brian left a heartfelt post to his long-time friend.
“David McCallum was a mentor, a great scene partner, a wonderful father and husband, and he was my dear friend,” Brian wrote on Instagram.
The lovely post below shows how much David meant to Brian, and he details their friendship on and off the screen. Brian also shares several pictures.
“Thank you David. Love you, my friend. I’ll miss you. Sending all my love to the McCallum family today,” Brian concluded his post.
More NCIS stars write messages about David McCallum
Katrina Law (she plays Agent Jessica Knight) left a simple post for David.
Actress Pauley Perrette (she played Abby Sciuto) left a kind message for David.
Pauley also shared numerous flashback photos from their time together.
Former NCIS star Lauren Holly (she used to star as NCIS Director Jenny Shepard) shared her love on Twitter.
Michael Weatherly (he used to play Agent Anthony DiNozzo) wrote several posts on social media.
In the post below, Michael raises a jug to celebrate him.
More NCIS news
NCIS has been on hiatus due to the ongoing Hollywood strikes.
But some good news from the WGA may lead to NCIS Season 21 episodes arriving soon.
Very soon, a new NCIS spin-off will debut on CBS.
During the downtime, NCIS and its spin-offs are available for viewing online.
NCIS is streaming on Paramount+