Big Brother twist: Sarah Jane Adams and Mary Kalifatidis sent to a secret room after an eviction

It’s ‘Surprise Week’ in the Big Brother Australia house.

And on Tuesday night’s episode, two housemates were in for the shock of their lives when an epic twist was introduced.

Sarah Jane Adams and Mary Kalifatidis thought their time on reality TV had come to an end with a double eviction, but they were actually sent packing to a secret room.

Plot twist: Big Brother’s Sarah Jane Adams, 66, [L] and Mary Kalifatidis, 55, [R] were sent to a secret attic after shocking double eviction during Tuesday night’s episode

‘My house has surprises around every corner, but did you ever think to look up?’ the mysterious Big Brother voice-over told the 66-year-old antiques dealer. 

A metal ladder was then shown being lowered from the corridor ceiling, as Big Brother continued: ‘What happens in my attic will turn the game on its head.’ 

Earlier in the episode, Sarah Jane and Mary, 55, were evicted by their peers.

Look up! ‘My house has surprises around every corner, but did you ever think to look up?’ the mysterious Big Brother voice-over told the 66-year-old antiques dealer

Who knew? A metal ladder was then shown being lowered from the corridor ceiling, as Big Brother continued: ‘What happens in my attic will turn the game on its head.’

SJ was eliminated first after a receiving a staggering eight votes.

Big Brother then surprised his housemates by revealing there will be a second eviction.

They had to vote again between Mary and Sid Pattni. 

Company: Big Brother then surprised his housemates by revealing there will be a second eviction. They had to vote again between Mary [pictured] and Sid

Going up! It was a draw so challenge winners Daniel Hayes and Christina Podolyan had to make the final decision. They choose Mary who ended up joining SJ in the attic

It was a draw so challenge winners Daniel Hayes and Christina Podolyan had to make the final decision.  They choose Mary who ended up joining SJ in the attic.

The attic space is the second secret room to be unveiled so far this season.

During week one, Daniel Hayes and Nicholas Benton snuck away to an underground boiler room for two nights and were exempt from the first eviction. 

More secret rooms: During week one, Daniel Hayes (left) and Nicholas Benton (right) snuck away to an underground boiler room and were exempt from the first eviction