Half a century into his career, and the king of Spanish cinema is still working on his Mommy Issues.

‘Parallel Mothers” gives us Pedro Almodóvar in his 70s, past the rambunctious, liberating and boundary pushing cinema of his “Women on the Verge” youth, a gay filmmaker who grew up in the fascist Spain of Franco coming to grips with his own legacy and his country’s.

He does it by marrying a story of single-motherhood and the loss of a child with a family history of single moms, the first of whom was given that status when a fascist hit squad made her husband disappear. It’s a brilliant conceit that invites us to read in Almodóvar’s own history and what he himself sees as his legacy — movies, many of them brilliant, but no children to carry on the family name.

Almodóvar considers this through his protagonist, Janis (his longtime muse Penélope Cruz), and cleverly compares the loss she feels in the present day with the lingering pain generations of her family carry over the lack of closure with their murdered ancestor in a country that’s tried to reconcile its murderous Catholo-fascist past and move on.

Janis is a fashion and magazine photographer in Madrid who meets a forensic anthropologist (Israel Elejalde) on an assignment, and proceeds to tell him her family’s tragic history, the ancestor taken from his home, shot and buried in a mass grave outside of the small town where she grew up.

She knows where the bodies were buried. Everyone there does. But no one — official or informal — has dug up the dead, identified them and given them a proper burial, leaving this an open wound that has spanned generations for everyone related to someone buried in that grim, unmarked memorial to the Spanish Civil War.

Arturo can help. It doesn’t hurt that Janis is a knockout. That’s how these two, thrown together by tragedy and work, wind up in bed with an “accident” putting Janis in a shared maternity room with teenaged Ana (Milena Smit) some months down the road.

Ana is also facing childbirth as a result of an “accident.” But Janis doesn’t “regret” hers. Ana does.

They bond, with Janis pitching in on the mothering that Ana’s self-absorbed actress-mother (Aitana Sánchez-Gijón) isn’t doing, and give birth to babies with just a hint of “complications” that put them in the observation ward.

It isn’t until Arturo, now out of the picture, asks to see the baby that Janis starts to wonder about the tyke that her best friend (Rossy de Palma) has already described as a bit “ethnic,” code for darker Latin American “Indian” genetic traits.

“I don’t recognize her,” Arturo tactlessly declares. He doesn’t think it’s his. Janis is furious. A flashback shows how she made an earlier break from Arturo on telling him the news of her pregnancy. She wants nothing from him.

“I will be a single mother, like my mother before me, and her mother before her!” (in Spanish with English subtitles).

But as angry as she is, she has eyes and Internet access. One genetic test kit later, she has her answer. It’s just that she doesn’t tell anyone. She simply cozies up to Ana, and changes her phone number to avoid telling Arturo he was right.

Almodóvar’s films, even the comedies, have soap operatic melodrama woven into their stories. “Baby switch” is classic soap stuff, and much of what follows only “works” in that sort of par-for-the-course soap universe.

But keeping his camera tight on Cruz, he tells the story of her agony with her eyes and the occasional tear. If she’s manipulating Ana and keeping Arturo at arm’s length, she has her reasons.

And every reminder of the lone “connection” she has with her baby daddy — that hoped-for uncovering of, identifying and re-burying her ancestor — reminds us of the legacy of pain and loss that is her shared lot with millions of present-day Spaniards.

Almodóvar does an adequate job of marrying these two disparate stories, even if he has to skate past gaps in the logic and clumsily-handled flashbacks.

But he hitched his wagon to Cruz wisely, all those years ago. She makes us feel every gut-punch loss Janis faces and bears up under. That keeps us going through the absurd and ever-so-Almodóvar sexual twists and turns in the tale, and keeps us engaged until the picture’s intensely moving payoff.

This isn’t one of the filmmaker’s great films, but it is a serious return to form and a movie that makes us feel the pain of women — in childbirth. in disappointment and in loss — as intensely as he does.

And that, for those who’ve been paying attention, is his legacy.

Rating: R, for some sexuality

Cast: Penélope Cruz, Milena Smit, Rossy de Palma, Aitana Sánchez-Gijón and Israel Elejalde

Credits: Scripted and directed by Pedro Almodóvar. A Sony Pictures Classics release.

Running time: 2:03