Mark Harmon’s Heartbreak Over ‘NCIS’ Death!

Mark Harmon took the death of his beloved friend Gary Glasberg — the “NCIS” creator and show runner – especially hard. The cast of the hit drama was rocked by their boss' sudden death on Sept. 28, 2016, at the age of 50. An exclusive source close to Harmon has now told RadarOnline how losing Gary literally left the star of the world’s most popular show at a loss for words.

“Mark’s wife Pam said he almost didn’t speak a whole sentence for about two days after Gary died because he was in such disbelief and sadness,” the insider told Radar. “He wanted to be close to Pam, but didn’t want to talk about what happened.” Harmon was especially torn up over his co-worker’s sudden passing because he “never said ‘goodbye.’”

“Mark’s wife Pam said he almost didn’t speak a whole sentence for about two days after Gary died because he was in such disbelief and sadness,” the insider told Radar. “He wanted to be close to Pam, but didn’t want to talk about what happened.” Harmon was especially torn up over his co-worker’s sudden passing because he “never said ‘goodbye.’”

Insiders added that Gary's sudden death was also a cruel reminder of how quickly Mark lost his own father — legendary sportscaster Tom Harmon, who was also a war hero and winner of the Heisman Trophy. Tom was stricken by a fatal heart attack at the age of 70, just moments after winning a golf tournament at Bel Air Country Club in 1990.

Friends added that Mark's also become increasingly concerned about his own health, with the star having turned 65 on September 2, 2016. That was just weeks before Gary's sudden death. Said an insider: “I wouldn’t be surprised if he’s convinced he’ll die soon from heart disease — just like his dad!”