Fitfully amusing and unfailingly sweet, “All Happy Families” is a rom-com that pleasantly passes the time to a sitcom beat. It’s also topical — sexual harassment and gender dysphoria come up — and it’s sensitive, which reflects the baggage of its star.

Josh Radnor’s “How I Met Your Mother” may have uneasily walked the line between romantic and cringey between its mostly unsubtle laughs, a series that felt instantly-dated. But Radnor came through it largely unscathed, easily cast to this day as a guy too much in his head, uncertain and “blocked,” but a true romantic at heart.

Here, he’s Graham, a failed Chicago actor well in his ’40s, still going on auditions, still living rent-free in the house where he grew up, a place that could very well fall to ruin on his watch.

Graham’s more successful actor-brother Will (Rob Huebel, dryly self-absorbed and contemptible) bought the house from their parents and lets Graham run it and insists he “use my name” when trying to rent the bottom floor, “because people LOVE my show.” That would be his soapy family drama “Winsome Falls.”

Will’s the kind of sibling who drops in for an unannounced visit, let’s slip that his son has come out as his daughter (Will’s divorced) and still tries to make his whole visit about himself.

Even taking Graham and their parents (Becky Ann Baker and John Ashton) on a Chicago River tour boat ride becomes another place to showboat his TV fame.

But the house has a basement that floods and needs all new plumbing. The rentable half is a mess. An old college classmate (Chandra Russell), now a chef who makes Graham’s heart skip a beat, wants to lease it.

Mom just retired, and her sleazy employer groped her at her retirement party. Dad’s still working with a bad back, a drinking problem and an even worse gambling one.

And that Stephen Collins vibe we got from Will’s scenes in “Winsome Falls” comes home to roost as he’s publicly-accused. VERY publicly.

A sitcom season’s worth of “drama” befalls the Landry clan, with Graham bearing the brunt of too much of it, not all of it with good humor.

What plays here is how easy this family is to buy into. They bicker like real siblings, a real married couple and a real family

“I hate you!” “I love you!”

Dad’s an out-of-step Neanderthal who uses phrases like “Don’t get your panties in a twist” and clings to notions like the missing “father figure” contributed to Will’s kid’s gender confusion. Mom’s put up with a lot from all of them, and is living with the frustration of her own performing arts dreams. We see and hear her duet with Rodney Crowell in a pub scene, at one point.

There’s a lot that feels incomplete here, introduced and abandoned or at least never wrestled with. And much of what transpires after the assorted ingredients are introduced is utterly predictable.

But Radnor is in his wheelhouse with this character, and the supporting cast sparkles. Colleen Camp plays Graham’s long-suffering agent, Natalija Nogulich the stereotypical Russian neighbor, Antoine McKay a pushy plumber and Ivy O’Brien the classically brassy barmaid.

So what if it’s a more than a little sitcommy, if the big “twist” is too on-the-nose and left hanging, along with the troubled parental marriage and the unresolved #MeToo cancellation? “All Happy Families” plays. And Rodney Crowell and Broadway’s Becky Ann Baker sing. That’ll do. That’ll do nicely.

Rating: unrated, fisticuffs, drug use, sexual harassment, profanity

Cast: Josh Radnor, Chandra Russell, Becky Ann Baker, Rob Huebel, Colleen Camp and John Ashton, with Rodney Crowell.

Credits: Haroula Rose, scripted by Coburn Goss and Haroula Rose. A Freestyle release.

Running time: 1:30