Dawn French thought the Queen Mother was a "witch" when she first met her.
The 59-year-old comedienne had "nightmares for years" when she saw the late royal - who died in 2002 - at the age of three because of her "virtually black teeth."
Speaking in her stand-up show, 'Dawn French Live: 30 Million Minutes', she said: "We commenced our well-practised bowing and curtseying. And what happened next was the stuff of my nightmares for years to come, because as I arose from my rather well executed curtsey, the Queen Mother smiled - and she had virtually black teeth. Black teeth, like a witch. Believe me when you're three years and nine months old, black teeth equals witch. I couldn't believe that a queen witch is coming into my house and nobody was doing anything to stop her.
"I was utterly dumbstruck and refused to look at her or talk to her for the entire rest of the visit. It was quite simply the most terrifying half hour of my life."
Dawn met the royal after her father Denys - who was an RAF sergeant - was chosen to host tea for the Queen Mother during a visit to his base in Yorkshire in 1961.
In archive footage, screened during the funny woman's show, Dawn can be seen wearing a yellow cardigan as she shook the royal's hand outside her home.
However, after she spotted her dirty gnashers, she refused to talk to her again.