Despite some resonant moments, Ricki and the Flash does suffer from scenes that belie believability. For no good reason, Ricki, who spends most of the movie in chains and boots, tattoos and too much eye make-up, is a staunch Republican. She’s ignorant at best, bigoted at worst. She criticizes Obama, apologizing to her single black bandmate, and expects her gay son will choose to be straight sooner or later. Her more conservative family, meanwhile, is actually more liberal, which I’m sorry to report, is demonstrated by a penchant for overpriced organic food. A mildly interesting twist? Maybe, but not necessary and a false note in an otherwise sincere story. I also had a problem with the idea that a woman who would bother to buy a modest pale blue polyester mother-of-the-groom dress at her local Good Will would arrive at a wedding with cornrows in her hair. The disapproval of the other guests — like Ricki’s ill-advised hairdo — went way too far.

Kevin Kline, Streep’s co-star many moons ago in Sophie’s Choice, plays her ex- with bittersweet resolve. He is comfortable but misses her as is revealed in the obligatory old-people-smoking-dope scene (what is up with that trend?). Kline is an incredible actor and should have been given more to do. It would have been nice to see him lose it. Meanwhile, his new wife is played by multi-Tony Award winner Audra McDonald. As always, she turns in a solid performance as Maureen (or “Mo”), the woman who stepped up when Ricki stepped out. She is particularly sharp in one scene where she confronts Ricki post-shower, dismissing Ricki’s concern that she’s “practically naked” and thereby giving herself a distinct upper hand. But McDonald, like Kline, is overshadowed. This is, after all, Ricki’s story. More important, it’s Streep’s movie. Step aside, folks, step aside.

Then again, is there anything Meryl can’t do? She’s sung in films before. Not just Mamma Mia, but Postcards from the Edge. And A Prairie Home Companion. And Silkwood. And Into the Woods. And now we can all rest assured that she could have been a bona fide rockstar. She’s also expert at changing herself — physically, vocally, utterly — to fully become someone else. And yet she remains Meryl Streep. Often referred to as the greatest actress of her generation (or, maybe any), her talent is such that we might be able to forgive her for abandoning her own family to pursue her calling. Yet, she didn’t. In addition to her unparalleled acting chops, Streep is admired for her even-keeled mothering. Her children, by all accounts, are sensible, hard-working and talented in their own right. And one of them shares the screen with Streep in Ricki.

Mamie Gummer plays depressed daughter Julie and while her scenes (like Kline’s and McDonald’s) are too few and too brief, she absolutely shines on the screen. Whether she’s berating her mother with an acute rage and fairly deadly aim, shakily watching her ex- and his new girlfriend through a pub window, or freezing with fear as she walks down the aisle at her brother’s wedding, she never hits a false note. Her intelligence and candor are mesmerizing. She reminds me of someone who took our breath away at a different wedding in The Deer Hunter nearly 40 years ago.

That would, of course, be Meryl Streep.