50 years ago—November 22, 1968—NBC aired an otherwise-forgettable Star Trek episode with an unforgettable moment.

Captain James Kirk and Lieutenant Uhura, under mind-control by aliens in a totally ridiculous plot involving adherents to Plato, kiss for a few fleeting moments.

The smooching scene has been commonly referred to as television’s first interracial kiss—but there’s compelling evidence that it actually wasn’t.

Still, this bisou remains an iconic Star Trek moment at a time in America when there were very few mainstream media depictions of mixed-race intimacy. After all, "Plato's Stepchildren" aired just 18 months after the Supreme Court decided the case of Loving v. Virginia, which overturned all bans on interracial marriage in the United States.

1968 was a turbulent year for race relations in America, to say the least, and saw the assassinations of both Martin Luther King Jr. and Robert F. Kennedy.

According to The Hollywood Reporter, the scene in "Plato's Stepchildren" was shot one way with the actors' lips meeting (as the show's creator, Gene Roddenberry, wrote it) and another where they don’t. However, actors William Shatner (Kirk) and Nichelle Nichols (Uhura) both flubbed the non-kiss takes so that the director (who was concerned about possible backlash) would be forced to use the real McCoy.

Nichols has spoken about the episode multiple times, noting that while there was some concern that the episode would spark protest amongst viewers, the reaction was generally positive. In a 2011 interview, she recalled the fans' response to the kiss.

"Apparently, this was the largest fan mail that Paramount had ever gotten on Star Trek for one episode" she said. "They were simply amazed."

Notably, Nichols remembered one particular letter that had been selected for her to read by Roddenberry himself.

"I opened it up, and I read it, and it said: 'I'm a white man from the South, and I'm against the mixing of the races. But anytime a red-blooded boy like Captain Kirk gets a beautiful dame in his arms like Lt. Uhura, he ain't going to fight it,'" she told an interviewer, before seeming to address the letter-writer. "Now what's wrong with that, boy?"

In the same interview, Nichols said that the episode remains one of her favorites in the series.

By contrast, in 2009, Shatner called the kiss "a big to-do about nothing."