Appearing on Tuesday's This Morning, the Derry Girls star told Holly Willoughby and Phillip Schofield about the moment when she fell over in heels and Claudia Jessie, who plays Elouise Bridgerton, bore the brunt of it.
"With my corset and everything, I had no central strength so I just completely toppled over. It happened twice more - I fell over three times. And the third time I was carrying a parasol which, you know, held in the wrong hands is deadly weapon."
WATCH: Bridgerton heartthrob Rege-Jean Page responds to Bond rumours
She added: "So I fell forward really quickly and I stabbed Claudia Jessie in the hand and it drew blood - that was my first day. But she forgave me, we're still friends!"
Nicola, who's also known and loved for her role as Clare Devlin in Channel 4 comedy Derry Girls, also opened up about season two of the hugely popular show.
She told the presenters: "I mean, I hope so, we just have to wait for the gods at Netflix to say yes, but I mean when we got back to viewing figures it was just outrageous. You think 63 million households I can't sort of fathom that, it sounds unreal to me. So I'm hopeful, I guess!"
Nicola Coughlan and Claudia Jessie in Bridgerton
The Netflix series, created by Grey's Anatomy and How to Get Away with Murder writer Shonda Rhimes, has caused a stir since it landed on the streaming platform on Christmas Day 2019, in particular for its racy love scenes.
Star of the show, Regé-Jean Page, revealed he had given his family back home in London a heads up regarding some of the show's steamy moments via their family WhatsApp group. He also relayed the story of a funny message he had subsequently received from his cousin.
He told Jimmy: "She sent me a message that was like, 'I had to make so many tactical cups of tea during the show.' She said, 'I came back, and you were still going, so I had to go back and put the kettle back on'."
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