The show, which is broadcast on Thursday night will also be her first major TV appearance since her explosive interview with Oprah Winfrey in which the Duchess spoke of her unhappiness at her life in the Palace.

On this occasion the former Suits actress appears to be on less controversial ground, describing her days turning up for auditions in Hollywood.

Wearing a £1,336 Oscar de la Renta blouse, she paints a picture of her struggles as she tried to establish herself in show business.

“I had this very old Ford Explorer Sport and, at a certain point, the key stopped working on the driver’s side, so you couldn’t get yourself in through the door,” she says

“So, after auditions, I would park at the back of the parking lot and I would open the trunk and climb in, pull the door shut behind me and crawl all over my seats to get out. That’s how I would come to and fro.”

The Duke and Duchess of Sussex have largely restricted their public appearances to charitable events and promoting their Arch well foundation.