While a group of them are holidaying in the Maldives - all thanks to Stephanie Pratt - Tiff is forced to come clean to Sam about a lie she's been keeping.
In a sneak peek of next week, which was shown at the end of Monday's episode, Steph tells Tiff: "Why am I keeping all your secrets and being a good friend when you're not a good friend to me?"
Tiff replies: "Every day I think about this lie. Every day. I feel f**king awful."
Then another scene shows Tiff and Sam on the beach, with Sam holding his head in his hands as he says: "Argh, Tiff. You f**ked him."
In tears, Tiff apologises, "I'm so, so sorry. I'm so sorry," but Sam walks away.
Sam and Tiff have been solid this series, but they did end the last series on a bad note after Sam confessed he had been unfaithful. And earlier on in that series, Tiffany revealed that she had kissed someone else during a trip to Hong Kong in the summer.
Made In Chelsea - Mondays at 9pm on E4
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