The money will be taken out of the eventual winner's £100,000 prize fund.
Conor and Luke Scrase spent 79 hours this week in the White Room, having been told that they had to remain in there to have a chance of winning a pass to the Big Brother final.
Tonight (August 3), the pair were shown a counter with "£0" written on it, and told that the figure would increase for the duration of a minute.
They were then told that, if either of them were to press their buzzer during the minute, that person would win the amount shown on the counter, but would have to leave.
They were also informed that the money would be taken from the eventual winner's £100,000 prize fund.
If neither pressed their button, they would both go through to the final.
As the amount increased, Luke S counted 'Mississippis' in an attempt to time the minute.
When the figure of £50,000 was reached and Big Brother indicated that there were five seconds left, both pressed their buttons.
Luke S, seemingly thinking that he had taken the money, grinned at Conor. When Big Brother announced that Conor had in fact beaten him to the buzzer, both contestants held their hands to their faces in shock.
The pair then hugged and Luke S began to cry.
As the Derry contestant walked out with his winnings, Luke S said: "That would have been half yours [if I had hit the buzzer first]," to which Conor simply replied: "Don't worry about anything."
"I'm worried," Luke S said in return.
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Copyright: Channel 5