In the exclusive clip, Whittaker's character Tess asks Nicole da Silva's Simone what's happening with her novel, but she says she's no longer working on it.
She tries to get a plot synopsis out of her, but she simply tells her it's about two friends who fall in love but can't admit it, leaving Tess suspicious.
Meanwhile, Yael Stone's character Hat texts Simone secretly, telling her that if she spills the beans and tells Tess the truth, ruining Raf's party, she will "kill" her.
You can watch the first-look clip right above now.
The series first arrived Australia earlier this year, but is now about to arrive on Paramount Plus in the UK on Friday 24th November.
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Before this, Whittaker was most recently seen in Time season 2, in which she played a woman sent to prison for fiddling her electricity bill.
She will also be heard this Christmas in new Julia Donaldson adaptation Tabby McTat, which will air on BBC One.
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Whittaker recently reflected on her time as the Doctor in Doctor Who, saying that while she would feel uncomfortable starring in a straight comedy, the blend of genres allowed her to play a character closer to herself.
She said: "That character made my life because I was allowed every twitch and fidget that I usually have to rein in.
"Drama terrifies me, but there's a comfort in the fear. I do love to find the humour in whatever I do, though, because you can't have three hours of misery."
One Night is coming to Paramount Plus on Friday 24th November - get a seven-day free trial of Paramount Plus on Amazon Prime Video.
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