Mark Harmon is being lined up for a full-blown return to NCIS to save its dwindling ratings. The National Examiner can reveal the vet is willing to do whatever it takes to save the beloved franchise that’s defined his career.

Sources point out that the original series has fallen to No. 10 on the top TV show list, and now bosses are in crisis mode.

Mark believes he can keep the military action drama that he’s poured his heart into from going down the drain, says an insider.

The show — which he also executive produces — “has sunk in the ratings for the first time, and people are nervous and seeing that as a bad omen of things to come,” the insider says. “Mark coming back — even on a recurring basis — would save the show.”

However, there are some cast members who aren’t exactly keen on Mark returning, says the insider. “People are complaining he’ll be throwing his weight around and telling them what to do. He does enough of that already as exec producer.” But those backstage gripes don’t seem to faze the Freakier Friday star.

“Mark doesn’t really care who he pisses off, because if the ratings are bad, then he has every right to come back to save it,” says the insider. “He worries it’ll go down the drain otherwise. Mark will be making his presence more known than it already is.”

Mark, 73, played Special Agent in Charge Leroy Jethro Gibbs of the Naval Criminal Investigative Service for 18 seasons until leaving NCIS as a regular character in season 19.

Besides having his executive-producer duties on NCIS, Mark also serves as an executive producer and the narrator on the spinoff NCIS: Origins, which revolves around the younger Leroy Jethro Gibbs, played by Austin Stowell.

“Mark already had one cameo on NCIS: Origins, and it’s been teased that he may appear on that show again,” the insider says. “Now he’s ready to come out of semi-retirement to raise the original NCIS from the dumpster. If anyone can do it, it’s Mark.”