Sam Thompson gets Sarah Harding to admit she snogged Chad Johnson in funny prank on Celebrity Big Brother

CELEBRITY Big Brother's Sam Thompson has caught out Sarah Harding over her snog with Chad Johnson.

The former Girls Aloud singer locked lips with the hunky American on last night's show before the pair were pictured cuddling in bed together when the rest of their housemates were asleep.

But in a preview clip, reality star Sam can be seen bluffing about what he knows, leading to Sarah unwittingly revealing the truth about their clinch.

As a group of celebrities sit in the garden, the 25-year-old said: "Sarah, Sarah, I saw."

Trying to keep a straight face, Sarah replied: "Oh f***, no. No you didn't see anything.
"You didn't see anything, I don't know what you're talking about."

But when Sam replied he went for a glass of water, Sarah's face visibly dropped and she asked: "When?"

Sam remained silent and after a pause, Sarah gave the truth away, saying: "It was a one off. Thank you. Emotions were very high."

The group made surprised noises at the revelation, before Sandi Bogle and Jordan Davies debate what Sam had seen - also failing to realise he was bluffing.

Sandi said: "It's not that bad then. Her leg?"

Twisting things further, Sam said: "I will keep it schtum."

Looking horrified, Sarah replied: "It was nothing like that. It was nothing that extreme."

Sandi then asked: "You was kissing?" and Sarah's face told them everything they needed to know.

Sam said: "I knew it, I knew it" and when Sarah said it was a "one-off" he finally revealed the truth, saying: "I didn't even see anything!"

The 35-year-old collapsed against her beanbag in dismay as everyone screeched with delight at Sam's detective skills, with Jordan shouting his mate was a "legend".

As he jumped around the garden with excitement, Sam shouted: "I knew she did it. I am such a legend!"

Jordan replied: "Sam that was so good".

A mortified Sarah tried to explain herself, and said: "It's just emotions were like...."

Sam continued his celebrations before sitting back down, and Sarah asked: "So why did you say you went for a glass of water?"

Jordan replied for his pal, saying: "He was bluffing".

Pulling a face, Sarah said: "You're such a s**t."

Composing himself, Sam replied: "Let me tell you my thought process, I saw something 'cause I just thought maybe there's a chance then you started acting weird and I was like well it either happened in the kitchen or the bedroom.
"So I was like I went for a glass of water."

Sarah held her head in her hands as she realised what had happened, but the group reassured her that it was OK.

Jordan said: "Don't worry Sarah, you like him, he likes you so it's alright", while Sam added: "Yeah he likes you a lot."

But the cheeky star couldn't help a final tease, asking: "Did his beard bristle against your..."

Sarah, looking like she wanted the ground to swallow her up, replied: "Oh f*** off!" but Sam was relentless, adding: "Did it tickle your top upper lip?"

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