Stop me if you’ve heard this one before. New York City cop John McClane flies to a far-off metropolis to visit a family member and finds himself in the middle of a terrorist plot.

If Harvard Business School wants to do a case study on how to debase a once-respected brand, they needn’t look any further than the “Die Hard” movies. The triumphant 1988 debut was slam-bang, adrenaline-surging action with a rich vein of humor and a surprising amount of heart. With Bruce Willis cast as working-class hero McClane, the film gave us a welcome counterpoint to smoothie super spies like James Bond. With no weapons but his street smarts, he improvised a plan to liberate Nakatomi Towers from a band of sophisticated, well-equipped terrorists. You could hardly follow him through the building’s elevator shafts and heating ducts, picking off bad guys with surgical precision, without yelling “Yippie-ki-yay!”

Each succeeding film slipped farther from the high-water mark established by director John McTiernan. His successors never recaptured that special blend of rocket-launcher impact and clever, engrossing character study. Willis, who came to the first “Die Hard” as an untested TV star with a lot to prove, delivered progressively more complacent performances.

Now comes “A Good Day to Die Hard,” which puts McClane in Moscow amid a second-rate spy story with sappy trimmings of father-son reconciliation. He makes the trip to support his long-estranged son Jack (Jai Courtney), who’s facing a murder charge. What he doesn’t know is that Jack is a CIA agent who deliberately put himself in the courtroom as part of a plot to obtain a file with damning evidence against a Russian leader. At first the McClane reunion doesn’t go as warmly as John had hoped, but he and Jack regain their familial bond by shooting up platoons of anonymous henchmen. There’s nothing like working on a project with your kid.

Willis is in a lamentable phase of his career. Having proved himself a tremendously gifted actor in the right hands (revisit “Moonrise Kingdom” or “Looper” if you have any doubts), he often settles into interchangeable bald-man-with-machine-gun roles. Can anyone really distinguish between the characters he plays in “The Expendables,” “Red” or this film? McClane’s wit is tamped down even as the firepower is amped up. Director John Moore (“Max Payne”) is proficient with chaos and shrapnel — there’s a fine, metal-crunching high-speed chase across several Moscow expressways — but he hasn’t a clue what to do with actors. The script by Kip Woods (“The A-Team”) offers few performing opportunities. It’s a lumpy broth of exposition, explosions and sorry-I-wasn’t-there-for-you sentimentality.

Nor is there a strong villain for McClane to battle. The story takes a long time to reveal who the real adversary is, wasting time that should have been used to engineer a deadly duel of wits. Compare the uninspired “A Good Day to Die Hard” with the exhilarating “Skyfall” and you see the difference between pushing a franchise to riskier, more demanding highs and letting it slide. The father-son design of the film suggests that the “Die Hard” series might be set to pass to the next generation of McClanes. I’d say it’s a good day to call it quits.