NCIS Season 21: Wilmer Valderrama Pays Tribute To David McCallum Ahead Of Ducky Episode

The cast of "NCIS" is still mourning the death of David McCallum, the beloved actor who played Dr. Donald "Ducky" Mallard on the series for 20 seasons. With Season 21 now underway, the show will honor the late actor and his character on next week's episode, "The Stories We Leave Behind," which promises to be an emotional outing. Furthermore, Wilmer Valderrama shared a tribute to his former co-star ahead of the episode's premiere on February 19.

While speaking to Entertainment Weekly, Valderrama explained that both the fans and the "NCIS" family need this episode for closure, but it's also a reminder of the lessons he learned from McCallum on the set. "All the way up to the last scene I did with him, the dude knew what he was doing. He'd come in, and then they said, "Action," and he'd never drop a line. I mean, I was in awe, and it reminded me that we should always do more and that we should always swing harder."

Valderrama added that Brian Dietzen wrote the episode, and he's created a perfect farewell to Ducky that will take viewers on a journey. With that in mind, what can viewers expect from the show's upcoming tribute to one of its longest-serving characters?

The "NCIS" Season 21 premiere ends with the team receiving an upsetting phone call. The details of the call aren't divulged, but the shocked reaction on Alden Parker's (Gary Cole) face implies some heartbreaking news about Ducky. Meanwhile, "The Stories We Leave Behind" will see the team mourn the loss of their late colleague by tackling a case that was significant to him, which involves a woman who was dishonorably discharged from the military.

While the "NCIS" cast and crew are keeping the surprises close to the vest for now, showrunner David J. North has revealed that the episode will explore each character's relationship with Ducky. "The case was important to Dr. Mallard. In [investigating it], they're going to relive their memories of a co-worker and a man who meant so very much to them," he told TV Insider, adding that it forces the team to think like Ducky.

North also noted that Brian Dietzen cried while writing the episode, and the cast and crew did the same while they were shooting it. Viewers will undoubtedly respond in a similar way, but it sounds like everyone involved was out to give Ducky the best tribute possible.