Anyone who's watched the hit Apple TV+ series "Severance" knows that it takes inspiration from many, many pop culture juggernauts that came before it. "Lost" is absolutely a reference point for the show's creator Dan Erickson, as is the famous anthology series "The Twilight Zone" — and apparently, a very specific installment of another anthology show, "Black Mirror," helped Erickson come up with the idea for "Severance."

The episode in question is "White Christmas," a standalone episode of "Black Mirror" that aired on the British network Channel 4 and was broadcast in the United States just before the entire series moved to Netflix for all future seasons. In an interview with The New York Times in 2022 after the first season of "Severance" concluded, Erickson said that "White Christmas," which came out in 2014, was such an unsettling episode that it gave him some ideas for "Severance" — specifically thanks to the fact that,...