{shortcode-783dd7087d30162c78d445a2eb359d80a3a4c698}There’s a popular theory circulated on Internet fan forums that suggests that all episodes of “Black Mirror” occur in the same universe. The concluding episode of Season Four of “Black Museum,” seems to confirm this hypothesis, featuring Easter eggs from nearly every episode in the series.

Structured similarly to “White Christmas,” which featured three nested stories, the episode begins with Nish (Letitia Wright) stopping by the titular Black Museum, a roadside collection of interesting items. Only instead of dusty antiques, the Museum showcases “authentic criminological artifacts,” each with their own grisly history. There’s a webbed helmet that allows a wearer to transmit medical symptoms to another party, a teddy bear with its own conscious inhabitant, and most horrifically, a digital captive, wrongly accused of murder, subjected to unending torture. “Black Museum” is the show at its most self-referential, a throwback kind of fan service. It’s a treat for dedicated viewers of the show, tending to rely on tried-and-true tropes of episodes past: stored consciousness, the nested, three-story arc that somersaults back to reference itself.

But to that point, “Black Museum” seems to be “White Christmas” Part II, an unwanted sequel. A rehashing of prior concepts, it might have succeeded if it had reassessed its subject matter, or revisited it in a different way. But it fails to say anything new. A worthy, albeit risky, direction could have pursued the mass incarceration angle: further exploring the symbolism of an innocent black man, unlawfully and eternally tortured, all for sadistic public entertainment and a profit. The “Black” in its title feels particularly pointed. After all, “Black Mirror” already tests the ethical limits of technology—why not justice, too?

—Staff writer Caroline A. Tsai can be reached at caroline.tsai@thecrimson.com. Follow her on Twitter @carolinetsai3.