Kids growing up in the ’60s found themselves a little shocked whenever some late night movie show on TV broadcast “Double Indemnity,” “The Caine Mutiny,” or anything starring TV dad and Disney comedy star Fred MacMurray playing a heavy.

He had a long career, and parlayed his stardom into investments that made him filthy rich. But it was still a a bit of a jaw-dropper to remember the befuddled looks and stammering and exasperation of his later roles — “My Three Sons,” “Son of Flubber,” “Kisses for My President” — had replaced steely glares and stacatto, film noir dialogue in roles that often used him as a cynical schemer.

MacMurray didn’t have that classic, sharp-edge stacatto of William Powell, Bogie and their ilk. But he could bowl through a line so fast you’d swear he was paid for how many words he could squeeze into 15 seconds of screen time. Here’s a blast from “Borderline,” his on-the-lam comic-thriller co-starring Claire Trevor.

“Looking for somebody?”

“No. Only the police, the Mexican federal men, Uncle Sam, several assorted hijackers and Pete Richey!”

This 1950 production is a chase through late ’40s Mexico, with Trevor’s Gladys Larue and MacMurray’s Johnny Macklin smuggling drugs in a big music box and the bottom of a parrot cage to contacts in sunny Southern California.

The film isn’t all that. But it’s more than a little reminiscent of Don Siegel’s far-better and darker “The Big Steal,” which starred Robert Mitchum and Jane Greer and released just a year before. And Trevor’s plucky and fun.

There’s historical value in seeing how much Spanish your average Angelino or the Gringo audience at large could speak or understand in a pinch, even then, when hustling South of the Border, and seeing Trevor literally elbow her way through the menfolk trying to talk over her, dismiss her and discount her contribution to their enterprise is a hoot.

That “enterprise” is a pre-DEA Federal drug enforcement team that lets an LAPD lass with WWII OSS (pre-CIA) experience talk herself into an undercover operation to catch some American crime Mr. Big, who runs his (heroin, apparently) operation from Mexico.

Director William A. Seiter got his start in the silents and went on to make “Belle of the Yukon” and “Allegheny Uprising” among his 150 or so credits. He presided over a Universal production that could look a tad under-designed. But when Trevor, as Madeleine Haley (her character’s “real” name) blurts out suggestions like “Why not a woman?” and the like, which the state, local and federal men she’s trying to tell how to take down “ladies’ man” Pete Richie stumble around until they think it was THEIR idea all along, Seiter shows he knows how to make a violent thriller funny.

The men bicker over her looks, right to her face.

“Naaah, Richey goes for tawdry, cheap-looking dames!” “She could pass!”

“She speaks pretty good Mexican!” her supervisor tells the Feds, and that seals the deal.

The plot parks “Gladys Larue” in a port city (Puerto Vallarta, maybe?) cantina chorus line, where she tries to keep up (no prob) and throw herself at the dark mug Pete Richie in a white suit, played by Raymond Burr. He’s not interested. It’s not until Richie gets a little rough with her that she and we realize she’s maybe got a shot with this “ladies’ man.”

She’s just photographed the guy’s contact list, after getting his top lieutenant good and drunk, when Richey’s plans are foiled by the two-fisted, torturing Johnny Macklin (MacMurray). He’s taking the drugs, for a bigger boss. He’ll get them across the border. The dame?

“Married couples” draw less suspicion.

The cross-country odyssey is dusty, fraught and peppered with Southern Cal locations doubling for Mexico and populated with Hollywood Mexicans — José Torvay, Nacho Galindo and Pepe Hern among them.

Burr makes a great heavy, as always, and renders cheesy threats like “I hope you haven’t got a good reason to live” credible.

MacMurray’s gift for screen sarcasm served him well in more serious parts.

“Forgot to tell you, I can also keep my mouth shut in two langauges!”

The picture gives away that his character is also in law enforcement far too early, and the few bursts of action make you wish they’d jammed in a little more.

But Trevor — of “Key Largo,” “Murder My Sweet” — makes this middling programmer worth watching, playing a character who is discounted, time and again because of her gender, but who always knows when to pull the trigger on that pistol she keeps in her tiny clutch, always seems to be passively “along for the ride” while actively saving their bacon, underestimated right to the end. Trevor would act will into the 1980s.

A bit more shooting and chasing and a little more style bechind the camera and “Borderline” could have crossed over “marginal” and into a near-noir that we’d consider part of the canon.

As it is, it’s the sort of movie that would tip MacMurray off that pictures like this weren’t going to tear Americans away from their TVs. He’d hit a last high water mark with “The Caine Mutiny” before picking up a pipe and widower’s sweater to finish his career in the comedies Golden Age Hollywood rarely let him tackle.

Rating: “approved,” violence, drug content

Case: Claire Trevor, Fred MacMurray, José Torvay, Nacho Galindo, Roy Roberts, Pepe Hern and Raymond Burr

Credits: Directed by William A. Seiter, scripted by Devery Freeman. A Universal release on Tubi, Youtube, Amazon, etc.

Running time: 1:31