Lena Olin earns a fine showcase as the partner, organizer, caregiver and maybe muse of a famous artist in “The Artist’s Wife.”

This domestic melodrama from producer (“Call Me by Your Name”) and sometime director (“Last Weekend”) Tom Dolby touches on the artistic temperament, thwarted ambition, family estrangement and dementia in covering just a hint of the same ground that Glenn Close took an Oscar nomination for in “The Wife” a few years back.

Married to ancient painter Richard Smythson, played by that colorful curmudgeon Bruce Dern, Claire (Olin) may have accepted her lot, to have to hear her famous husband say “I create the art” in interviews, and “She creates the rest of our life.”

For Claire, that means running their designer home and keeping his art dealer (Tonya Pinkins) placated, but at bay while Richard struggles for inspiration.

“It’s very hard to look inside and paint what’s all gone,” he confesses, at one point — not to Claire. Richard is still teaching classes, but his “erratic” behavior — vulgar around the students, insulting, unfiltered and forgetful — is causing problems.

Claire knows he’s “lived his life on his own terms.” But he was rash and temperamental to start with. Now, he’s losing it. Her new duty is keeping the peace with the college and his impatient dealer, and not telling him about the dementia his doctor sees settling in.

She is overwhelmed. In his sentient moments, he’s a joker. Their marriage is “Twenty-five years of ‘Stop, please,” he cracks in public. But she’s at the point of asking their housekeeper what it took for her to end her marriage.

Claire could use some support. Sure, the reason she starts hassling Richard’s estranged daughter (Juliet Rylance) is “I want him to remember you.” But taking on these end-of-life decisions for a famous and famously-irascible husband is hardly a burden you want to bear alone.

Angela is a mother, going through a break-up of her own, and not interested. But Claire is nothing if not persistent. Some of the best scenes of “The Artist’s Wife” are ones where we find how seriously estranged those two have been, and Claire’s cluelessness, caught in between them.

She doesn’t even know Angela’s sexual preference, has never met her little boy.

The three-writer screenplay is on its sturdiest ground letting a fine cast get across love, devotion, schisms and pain. Olin has always been an open book as an actress. And Dern’s later years have given him plenty of showcases for his mercurial twinkle-to-tirade range. Stephanie Powers has a chewy bit part as an old artist friend of the couple, and Avan Jogia has a little to play with as Angela’s calm-troubled-waters nanny.

The script lacks much of the couple’s back-story. Was she his student? And it develops a hitch in its step all throughout the third act, where abrupt character reversals give away every contrivance.

This is more worth seeing for Olin and Dern’s tetchy and touching interactions, portraying a marriage of devotion and decay. Every filmmaker who preaches that “Casting is everything,” or 90 percent of everything, isn’t exaggerating. “The Artist’s Wife” proves it.

MPAA Rating: R for language, some graphic nudity and brief sexuality

Cast: Lena Olin, Bruce Dern, Juliet Rylance, Avan Jogia and Stephanie Powers.

Credits: Directed by Tom Dolby, script by Tom Dolby, Nicole Brending and Abdi Nazemian. A Strand release.

Running time: 1:34