“Striking Vipers,” an entry in Black Mirror’s fifth season lineup, has an idea. Maybe two ideas, if you squint.

On the one hand, the installment, written by series creator Charlie Brooker, explores the blurry line between the digital self and the physical, the lives we live online, and the very real emotion they can bring into our daily existence. On the other, it brushes lightly against the friction between the American dream — two kids, two cars, a house, a monogamous straight marriage — and queer desire.

Without much to say about either dynamic, “Striking Vipers” relies on a sketchy script and the provocative nature of its gender-and-sexuality-blurring, sci-fi conceit to stretch maybe 11 minutes of thematic content like boardwalk taffy.

After drifting apart over the years, best friends Daniel and Karl reunite and bond through the Mortal Kombat-esque fighting game Striking Vipers X. The game has evolved since it’s button-smashing incarnations: now it’s played in a simulated virtual reality where players inhabit and feel the bodies of the characters. When Daniel and Karl enter the world, their relationship quickly takes a turn for the physical. Both men are frightened and compelled; the episode doesn’t dig too far into why.

Living and interacting from behind a digital proxy affords us the opportunity to imagine other versions of ourselves, to expand our concept of the forms we could inhabit and the ways our lives could look. These experiences, as any trans or gay person who grew up online could tell you, can be life-changing. “Striking Vipers” flirts with that kind of personal discovery, but ultimately shies away from it, preferring instead to dangle the possibility of subversive statements before withdrawing into the unspoken norms of heterosexual American culture. In one scene, Karl comments that occupying a female avatar within the world of the titular VR-enhanced video game feels more profound to him than his entire life’s experience as a man, but it never comes up again.

It’s clear Brooker has sex and gender on his mind, but by relentlessly folding both back into straight culture whenever the characters deviate from the episode’s norms defangs any statements it might make. At one point “Striking Vipers” even takes time out to reassure us that the relationship at its center isn’t really gay.

Anthony Mackie’s turn as affluent suburban dad Daniel is one of the flattest in the series’ long history of purposefully low-affect leading men. His emotional reticence is presented as his sole character trait, which at least gives him a leg up on his wife Theo, played by Nicole Beharie, who has none. Yahya Abdul-Mateen II is much livelier as the gregarious, mischievous Karl, but his energy can’t puncture the thick film of the episode’s emotionally lethargic detachment.

Black Mirror’s studious blandness has always felt like a creative choice, a way to allow viewers to imagine themselves more easily in the fictional worlds and scenarios it presents. In this case, the emotional distance reads as more alienating and dull than easily inhabited. The episode’s portrait of monied, emotionally tepid domestic life in “Striking Vipers” feels wholly disconnected from the circumstances in which queer sexuality and gender identity are most commonly explored through online immersion.

There’s precious little introspection about anything relating to self-expression or identity, and when the episode’s conceit finally comes out into the open between Mackie’s character and his wife we skip right over their conversation and any chance to see the inner emotional workings of these people. Worse, when Daniel and Karl meet in real life to see whether or not what they share within the game has any connection to their physical selves the show makes sure to confirm there’s no homosexual funny business going on here. Then they have a repressed fistfight, which in a more thoughtful episode of television might have led somewhere but which here stinks of racist stereotyping.

Ultimately, like most of Black Mirror, “Striking Vipers” is more reactionary than exploratory, imagining not how technology could change the way we love each other and explore ourselves but how it might interfere with mainstream culture’s dominance. The “happy ending” reasserts the inconsequential nature of queer desire and the supremacy of the heterosexual nuclear family, its overtures toward open-mindedness lost to backtracking and minimization.

If the episode dug into the emotions underlying its scattered sex scenes there might be something in it worth remembering, but without that vital human link, it’s just smug box-checking and white noise.