Movies that bend the laws of space-time without the introduction of a black hole fall more into the realm of fantasy than “Interstellar” science fiction.

It’s why films like this year’s “The Call” or “Frequency,” “The Time Traveler’s Wife” or “Somewhere in Time” should never bog themselves down in “explaining” how a woman moving into a house gets calls from somebody murdered there years before, or a son finds a radio that lets him talk to his dead dad, or why a woman is able to converse with a kid via his CRT TV and camcorder in 1989 and prevent his death in “Mirage.”

Oriol Paulo’s Barcelona-set thriller burns more screen time with characters trying to reason out the impossible than it should, and dawdles in other ways. But the mystery at the heart of it is fascinating and unraveling it is suspenseful, with life-and-death stakes that go beyond merely preventing a murder.

“The flight of a butterfly can be very cruel if it occurs in a place and a time that allows for change,” a character muses in this story (titled “Durante la tormenta” in Spanish), long after we’ve figured out what we’re witnessing is a Spanish tale wrapped up in “the butterfly effect.”

Vera (Adriana Ugarte), husband David (Álvaro Morte) have just moved into a house with their little girl. Tucked in an attic, they find a pre-HD cathode ray tube (analog) TV and VCR. And in the middle of a thunderstorm, Vera sees it flicker to life with images of a tween (Julio Bohigas-Couto) practicing Cyndi Lauper’s “Time After Time” on his guitar.

In his timeline, the kid is keeping himself entertained while his single-mom is at work, and all that’s on TV news is the collapse of the Berlin Wall. It’s 1989.

Vera is chilled to the marrow, as are we, the moment young Nico stares into his set and speaks to her. When she Internet searches the child, she discovers a murder Nico stumbled into that very night, a murderer foiled in the act of disposing of his wife’s body, a discovery that cost Nico his life.

When Vera reaches out again during a storm that mimics the one Nico lived through that night in 1989, she manages to warn the confused and frightened child. And damned if her pleas don’t save his life.

But when Vera wakes up the next day, she can’t pick up her kid from school. Nobody knows a “Gloria.” Dashing into her husband’s office, he doesn’t recognize her.

Nico surviving has changed history. The killer was never brought to justice. And Vera finds herself spilling her story to a sympathetic cop (Chino Darín), getting brain scans, talking to doctors and others about this recent novel that follows the plot of the story she’s telling.

And Vera, who was a nurse before, stayed in med school to become a neurosurgeon in this timeline, even if no one in their right mind would let her open a skull in her present (doesn’t remember finishing med school) state.

She must learn all she can about Nico and what might have changed and figure out how to correct this and get her daughter back, with pretty much nobody in her current timeline helping her or even taking her seriously.

Suspense comes from scenes where we see a little boy trying to reason out how to prevent a murder, or prevent the murderer from covering his tracks.

The script also tosses in lots and lots of twists, this thread making us question this peripheral character’s actions, that one connecting another character to the past and present in ways we don’t see. There’s even a hint of romance, of lovelife paths not taken, delivered in flashbacks.

Is this all in Vera’s head, a novel that’s gotten into her brain and taken over her life? Is she just a fictional character in that story?

“Mirage” takes its sweet time introducing those various wrinkles and seeing to it that too much is tidied up, folded in on itself. But that’s a big appeal of such time-travel/not-space-travel stories, the back-engineering involved.

The script may lose track of Vera’s driving impulse — getting her daughter back. But Ugarte, in a performance fraught with fear, desperation and focus, never does. She makes us believe and makes this work.

That’s the only “explanation” necessary in seeing through this mirage.

MPA Rating: TV-MA, violence

Cast: Adriana Ugarte, Chino Darín, Javier Gutiérrez, Álvaro Morte, Miquel Fernández, Clara Segura and Julio Bohigas-Couto

Credits: Directed by Oriol Paulo, scripted by Oriol Paulo, Lara Sendim. A Netflix release.

Running time: 2:08