However, the network was refusing to answer the big question: did they or didn't they?
According to the , Michelle, who is currently second favourite to win the programme outright, had her work cut out luring Stuart into the den she had created under the dining table, with cushions and sheets to give them privacy.
After he reluctantly agreed to her request to enter the den, he asked her "Are you just up for talking for a bit?"
Although Michelle agreed to talking, the pair soon got down to business, with the official website reporting there was an hour's worth of "muffled gasps, moans, some very intense toe curling and the odd whimper", following which Michelle emerged beaming.
The UK version of 'Big Brother' has, until now, remained sex free, despite the efforts of producers to get housemates to lower their guards. Stuart and Michelle's actions are bound to score high ratings for the show, which is helping Channel 4 to record some of its biggest audiences to date.
Earlier in the evening, the four remaining male housemates, Victor, Stuart, Dan and Jason, had to perform a striptease for the women's hen night as part of the ongoing wedding task. There will be a stag party tonight ahead of the wedding, which will see Shell play the bride and Victor the groom.
Prior to the hen party, at which the women drank Babycham to get them in the mood, Michelle had an argument with Stu because he refused to play the groom to her bride at the mock ceremony. Michelle will now take the role of a chorister, while 20-year-old Stuart will play the father of the bride.
Last night's episode of 'Big Brother' drew an average audience of 5.3m, peaking at 5.6m. The housemates nominated for eviction will be named tonight, with speculation that Scottish Jason will be one of those who face the boot.
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