We always knew how Bruce Willis would spend his celebrity dotage — Shakespeare in the Park, maybe a spirited farewell tour as “Bruno” with his band.

OK, maybe we didn’t. But seeing him in — BARELY in — C-movies like “Hard Kill” is just another reminder that some guys can’t let go, can’t change a lifetime of piss-poor movie choices and don’t know, the way Garbo and Cary Grant did, when it’s time to “close the door” and leave with their screen image intact and immortal.

“Hard Kill” is a garbage thriller made because the producers had access to an abandoned factory complex, a lot of tac gear to dress their color-coordinated “terrorist” minions in and Bruce Willis’s name.

Willis plays Chalmers, the billionaire ex-military chief of a tech empire who hires/tricks an elite mercenary team led by Derek (Jesse Metcalfe of “Desperate Housewives” and “Chesapeake Shores”) and Sasha (WWE minx Natalie Eva Marie) into helping him recover not just the story’s “MacGuffin,” a magical artificial intelligence gadget that “in the wrong hands” could doom us all.

And it’s in the wrong hands, those of the terrorist named “The Pardoner” (Lamest villain name ever, lamely played by Sergio Rizzuto).

Another thing in the wrong hands? Chalmers’ daughter Eve, the tech genius behind his Charterhouse Industries, is being held hostage. And I didn’t have to look up Lala Kent, who plays her, to realize she’s a no-talent, either a model or reality TV creation.

The fights and shootouts are fine, basically commandos taking out one helmeted minion after another.

The dialogue is limp as week-old Ramen, and the performances give “perfunctory” a bad name.

Willis? He’s just a wizened, pistol-packing bald guy who used to spend his holidays flying to LA, “having a few laughs,” a very long time ago.

MPA Rating: R for violence and language throughout

Cast: Jesse Metcalfe, Bruce Willis, Lala Kent, Natalie Eva Marie, Texas Battle and Sergio Rizzuto.

Credits: Directed by Matt Eskandari, script by Joe Russo and Chris LaMont. A Vertical release on Netflix.

Running time: 1:38