Viewers think they've spotted the moment when a Who Wants To Be A Millionaire contestant was cheating.

Charles Ingram was the ex-army Major at the centre of the famous 2001 cheating scandal during an episode of the ITV's renowned quiz show.

The legendary episode sees host Chris Tarrant ask Ingram the million pound question of: "A number one followed by one hundred zeros is known by what name?"

The options were A) Googol B) Megatron C) Gigabit or D) Nanomole.

After a long wait, Ingram 'decided' the correct answer of A) Googol.

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However, it later emerged that his wife Diana and accomplice Tecwen Whittock used cheating tactics which included coughing at answers throughout the show.

The trio were eventually found guilty of conspiring to cheat to win the £1m ($1.25m) jackpot.

Instead of winning £1million, the Ingrams' cheating cost them a massive £115,000.

After watching the footage back, some viewers think they've figured out the moment when the contestant gave up his master plan.

"If you've been watching this show closely for a long time, you'd notice that Ingram's behaviour is so much different than your regular contestant," one fan explained.

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"A non-cheating contestant would never risk his/her money if they have absolutely no clue what the answer is.

"The norm is to take the money and not risk it especially if the money won is a huge amount already. Ingram has never heard of 'googol' and yet he was willing to risk £480K on it.

"It doesn't make any sense. And you can tell that he was drawing blanks on most of those questions too.

"Now, compare him to John Carpenter who won $1M in the US version and you'll see how different their approaches were.

"John's way is how an intelligent player plays."

Another added: "The confidence he gains in explaining his choices once he's heard that cough is hilarious lol."

"His actual knowledge ended at £1,000," a third commented.

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Well, speaking about the scandal during an interview with The Mirror, Tarrant admitted that he 'had no idea what was happening' at the time.

"I'm sitting there, eyeball to eyeball with this guy and bearing in mind I've sort of been on telly all my life, it was probably one of the most amazing, forget about what happened afterwards," he said.

"It was just one of the most amazing TV shows I've ever done because people were screaming, shouting booing, gasping, applauding, standing, coughing because everybody coughs in television.

"I didn't notice this bloke about two inches away, looking behind them for a cough and all that, bearing in mind, the guy was a serving British Army Major in great big close-ups.

"You would never expect that to happen, would you?"