The record producer was called into the Diary Room on the morning of his 24th birthday and told that his track 'Winner' had been released by a bandmate during his time in the house and is expected to reach number one on Sunday.
However, as Anton listened again to his tune, Big Brother revealed to the watching housemates that the announcement was fake and they would now have to keep Anton convinced of his chart success.
"Remember housemates, it's all for Anton's own good," Big Brother assured them. "If he buys it, he'll have the day of his life and the perfect party and you'll be able to share it with him."
Watch housemates discover their secret mission below:
As part of the task, Big Brother will conduct a number of fake interviews with Anton for leading music magazines, before playing him a clip of Big Brother's Bit On The Side host Emma Willis interviewing his professional partner about the song's success.
All will be revealed to Anton tonight after he completes a live performance of 'Winner' in the Big Brother house, which will be followed by a spectacular party if housemates manage to pass their secret mission.
Big Brother has also made Anton 'King' of the Big Brother house in celebration of his birthday and chart triumph, allowing him to order around his fellow housemates as he pleases.
Watch Anton become King of the Big Brother house below: