WHO Wants To Be A Millionaire viewers were left baffled by a famous phone a friend.
Contestant Adrian stumbled on a question about the environment, which would up his winnings to £64,000.
Host Jeremy Clarkson asked the question: "In the natural world, the term 'nidification' refers specifically to the building of what?"
The options were webs, dams, reefs or nests.
"Hmmm, I don't really have any idea about this one. I think I'm going to have to phone a friend," Adrian said.
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"David Attenborough?" Jeremy asked.
"Sadly not, no," Adrian replied, "nearly as good, can I call Kevin please."
"Kevin Attenborough. Course, let's call Kevin Attenborough," Jeremy replied.
"What does Kevin do?" Jeremy asked.
"He's one of the Eggheads," Adrian nervously replied - which left Jeremy stunned.
"Oh is he? He's an actual Egghead? Oh, that's quite handy. Are you a quizzer?" the presenter asked.
"Well yeah, I bask in everyone else's glory," Adrian replied.
It took Kevin Ashman a matter of seconds to reveal the answer of nests.
Adrian asked if he was 100 percent, and Kevin said he was - leaving Adrian pretty pleased.
Luckily for the player, Kevin was correct and it pushed Adrian on to scoop an impressive £125,000 before leaving the show.
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But viewers couldn't believe that an Egghead was even allowed to take part in the show.
"Did the guy on Who wants to be a millionaire just use Kevin from eggheads as his phone a friend?" one wrote.
"Who wants to be a millionaire’ needs clearer boundaries. You can’t have an Egghead on call a friend when I’d be calling Dave from work," added a second.
"Guy on Who Wants to Be A Millionaire asks to phone a friend. Clarkson says "what does your friend do?" Turns out he is Kevin from Eggheads - one of the greatest quizzers in the world!" a third wrote.
"This guy on Who Wants To Be A Millionaire has Kevin off of Eggheads as his Phone A Friend. Cheat code completed," said another.
He's an actual Egghead? Oh, that's quite handy.
Jeremy Clarkson
This isn't the first time that two quiz worlds have clashed after Mark Labbett appeared on the programme.
He is known for being The Beast on The Chase, but before he was famous he once competed on Who Wants To Be A Millionaire.
During the episode, he was keen to point out he was single and told host Chris Tarrant he hoped his performance would boost his luck with the ladies.
Unsurprisingly Mark sailed through the initial few rounds, though had to use his first lifeline - Ask The Audience - at the £2K question, which was about knitting.
He then used his Phone a Friend lifeline to call his pal Mo when he couldn't decide which fruit was the principal ingredient of a traditional tarte tatin (answer - apple).
Mark provided some much-loved Beast banter along the way, telling host Chris that he was a school teacher and the kids were always coming up with nicknames for him - "King Kong" being one of them.
Mark continued: "Hulk, Godzilla - basically any time there's a monster flick, for some reason that's what my name becomes.
"I'm not even the tallest in my family - my little brother Phil is 6ft 8'."
He later admitted: "I can't intimidate the kids, but I can intimidate adults very easily."
