Mollie will be hoping she has what it takes to go all the way as she's faced by various challenges inside the scary perspex box to win cash for charity.
Bandmates Frankie Sandford, Una Healy, Rochelle Humes, and Vanessa White will be getting their pom-poms out to cheer Mollie on.
But will it be enough?
There's £250,000 up for grabs if she can go all the way, but does Mollie have what it takes to beat The Cube?
We can't wait to find out!
The Cube: Mollie King Celebrity Special, ITV, 7.30pm