By Candice Jackson For Daily Mail Australia
Published: 05:41 BST, 4 May 2021 | Updated: 05:41 BST, 4 May 2021
It's 'Surprise Week' in the Big Brother Australia house.
And on Tuesday, the housemates will be introduced to an epic twist.Insurance Loans Mortgage Attorney Credit Lawyer
Host Sonia Kruger has promised 'the most shocking surprise of all' in a sneak peek trailer released by Seven.
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Big Brother SHOCK twist: Housemates face 'the biggest surprise of all' on Tuesday as a secret room is revealed to stars. Pictured: Marley Biyendolo
'My house has surprises around every corner, but did you ever think to look up?' the mysterious Big Brother voice says in the clip.
Footage is then shown of a secret metal ladder lowering down from the corridor's ceiling, as he continues: 'what happens in my attic will turn the game on its head.'
The creepy dimly-lit space appeared