A lot of that is due to her natural beauty, of course, but the Duchess also had a little expert help with TV-ready hair and makeup, and her behind-the-scenes helpers were revealed via social media soon after the short video was posted online.
Makeup artist to the stars Daniel Martin shared an excerpt of the interviewer to Instagram that showed Meghan chatting and laughing with the talk show host.
In the caption, Daniel shared that he had applied Meghan's makeup, and also revealed her hairdressing team: Jason Low and the Highbrow Hippie salon.
WATCH: Meghan Markle to star in first TV interview since daughter Lilibet's birth
He wrote: "SURPRISE! My love on @theellenshowTomorrow!!! [heart and sunshine emojis]. Hair: @misterjasonlow @highbrowhippie. Makeup by moi."
Daniel Martin's other celebrity clients include A-list actresses Maggie Gyllenhaal and Gemma Chan, while Jason Low has worked with Bryce Dallas Howard and the Highbrow Hippie salon counts Julia Roberts and Kirsten Dunst among its high-profile clientele.
Meghan looked so glamorous in the teaser clip
Meghan's glossy dark hair was styled in loose waves that perfectly framed her face, while her makeup featured a neutral lip, rosy glow, and smoky eyes.
The Duchess made her return to television for her first interview since her baby girl, Lilibet, was born in June.
In the preview clip, she talked to Ellen about an unusual method she used of getting into and out of her old car.
"At a certain point the key stopped working on the driver's side... so I would crawl in the trunk and climb over my seats to get out... it was not ideal,"
The Duchess also looked stunning in New York last week
Meghan confessed. "Did anyone ever see you?" Ellen asked. Meghan responded: "I would play it off… just looking for my highlighters for my script... and then climb in."
She also revealed that arriving at the studio for the interview had been different in another significant way.
"The security guards would always say, 'Break a leg, we hope you get it,'" Meghan said.
"They knew you that well?" the talk show host asked. "I think they said that to everyone," the Duchess laughed.
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