One final twist turns the competition upside down in an explosive sneak peek for The Block 2023

After three long months, the contestants are almost done with The Block.

In a sneak peek for Sunday's final Room Reveals – which you can watch in the video above – host Scott Cam and the teams celebrate the milestone.

Stream every episode ever of The Block for free on 9Now.

"You've done it! You've finished The Block," Scott congratulates the teams at Block HQ.

They all clap and cheer after a sweat-inducing 12 week renovation.

While things are feeling good in Block HQ, that all changes very quickly when "one final twist turns the entire game upside down".

There is of course an $80,000 Mustang up for grabs for the winner of Front Yard Room Reveals and the contestants have stopped at nothing to give themselves the best chance possible.

Leah and Ash have been saving their bonus point gnome all season for this moment.

But earlier in the week Steph and Gian purchased another bonus point gnome from their neighbours Kyle and Leslie.

"Everyone now knows about this deal except Leah and Ash," Eliza reveals.

READ MORE: Here's everything we know so far about the Block 2023 auctions

The teams stand in a row as Scotty asks, "What about the gnome?"

Gian comes forward and says, "Yeah, we'll use it."

At this point Leah and Ash turn their heads in utter shock.

"You want to surprise us right there and then? For what gain?" Leah later snaps at cameras.

WATCH: 'Sorry mum': The Blockheads get matching tattoos to commemorate their final week

Scott Cam then announces the winner of Front Yard Week and the highly-sought after $80,000 Mustang.

But you'll have to wait until Sunday night's Room Reveals at 7pm to find out.

If the sneak peek is anything to go by, the Grand Final will reveal five spectacular family homes finished to perfection.

"This charming Aussie street is set for the transformation of a lifetime," the voiceover says.

WATCH: Every time Eliza made us laugh on this season of The Block 2023

While the judges are equally as impressed.

"This is an absolute showstopper," Marty Fox beams.

We. Can't. Wait.

READ MORE: The Block's auction history: How the order has impacted the results and winners

The Block airs Sunday 7.00pm and continues Monday at 7.30pm. The Block's Auction Grand Finale will air Sunday November 5 at 7.00pm on Nine and 9Now. Catch up on all the 9Now.

 Stream every episode ever of The Block for free on 9Now.