If this story were a TikTok video, the writer would be applying lip gloss right about … now. Unscrewing the cap on a tube of mauve goo and giving it a generous swipe across puckered lips. Mwah!

The application of lip gloss in the first few seconds of an online video is a subtle trick that creators and influencers use to grab attention — ideally without viewers’ even realizing why they were moved to stop scrolling.

And once you see it, you won’t be able to unsee it.

An influencer heading off to grocery shop at Erewhon in Los Angeles. A clip of the “Laguna Beach” star Kristin Cavallari sitting in her car lip-syncing. A nutritionist offering tips on how to curb your cravings.

What do these performances have in common? They begin with a lip gloss overture.

Julia Broome, a social media manager in Los Angeles, calls the makeup maneuver the “lip gloss tactic” and listed it among several other so-called subliminal hooks in a recent video. Other examples include starting a video while positioning the camera, to make it appear as though filming was just some spur of the moment idea, and wearing bracelets that click and clack in an aurally satisfying way, known online as an Autonomous Sensory Meridian Response, or A.S.M.R.

“It’s like doing a trick in front of your face and you don’t exactly know what’s going on, but you can’t look away,” Mr. Broome, 27, said.

She added that she had been using the lip gloss trick in her own videos, in which she regularly offers social media strategies and tips, when an eagle-eyed viewer called her out on it.

The viewer, Michelle Onorato, works in hospitality marketing. “When influencers do tactics like that, it makes you feel like you’re speaking to them personally,” said Ms. Onorato, who is 30 and lives in Miami. “It’s like a FaceTime call. You kind of get sucked into thinking you’re actually having a conversation with that person.”

Ms. Broome stressed that many of those who start their videos while putting on lipstick or lip gloss aren’t in the business of selling cosmetics.

“There are massive creators who use the lip gloss tactic as their hook,” she said, citing the popular influencers Paige Lorenze and Alix Earle. “They’re talking about something so completely different, and distracting you with their lip gloss. You can see half of the comments are talking about what she’s actually talking about, the actual meat of the video, and half of the comments section is like, ‘Where can I buy that lip gloss?’”

TikTok hosts an entire ecosystem of creators, like Ms. Broome, whose videos are designed to help aspiring influencers learn how to make content that the platform’s algorithm will favor.

Brittani Cunningham, a social media strategist and manager, said she advises clients to make sure they’re moving around while filming. “Just sitting in front of the phone or the camera can kind of get stale,” said Ms. Cunningham, who is 27 and lives in Fort Lauderdale, Fla.

Ms. Broome said she’s not worried that revealing these successful engagement strategies will make them any less effective.

“From a consumer perspective, it gives you a different lens to look through, like, ‘I don’t know if I want to be pulled into a video like that. I don’t know if I want to be manipulated to stay on someone’s page for this reason, or to be sold this product,’” she said.

Ms. Broome has more social media tricks up her sleeve. As with many online trends, she noted, by the time one has been firmly established another is poised to nudge it aside.

“Alix Earle does something all the time that I don’t think anybody has caught on to,” she said.

Ms. Broome kindly shared the something in question: Pretending to be running late, while hastily filming a video.