As mentioned, “Charades” is about how Spock is transformed into a human. After suffering a shuttlecraft accident, a species of noncorporeal aliens have to tend to Spock’s wounds. The species, however, is confused by Spock’s human and Vulcan DNA, and remix his genes to match the human Nurse Chapel (Jess Bush) who was traveling with him. Becoming human causes Spock to enter a tempestuous, adolescent state. His appetite for food increases, he is prone to fits of anger, and his libido increases. And his transformation is days before his distant fiancée is scheduled to visit … with her parents. Despite the sci-fi twist, this is a crisis worthy of a 1950s sitcom.
Jordan Canning pointed out that Spock needs to remain as Vulcan as possible most of the time, otherwise his human behavior in “Charades” wouldn’t read well. She described it thus:
“It’s kind of Spock’s teenage moment. […] But Ethan and I had to come up with ‘Spock scale,’ to make sure he didn’t get too human. A zero would be fully Vulcan. A five would totally human. We’d never want to see a ten!”
In “Charades,” Spock is at a five. In the original Trek, the character (as played by Leonard Nimoy) most often hovered between zero and one with occasional outbursts as high as four. On “Strange New Worlds,” he’s more of a 2, given his general friendliness. In the Kelvin-verse movies, Spock (as played by Zachary Quinto) is more solidly 6 or 7, appearing to be in a common state of anger and given to savagely beating bad guys on the roof of a speeding bus.