The penny drops and the contestants realise who's about to enter the MC kitchen.
A visit from Heston Blumenthal always produces unforgetable MasterChef moments.
The judges enjoy a spot of friendly MasterChef banter.
The contestants look on, unaware of who's about to make an Invention Test appearance.
It may be a high-pressure moment for the contestants, but the judges are laid back as ever.
The contestants watch in awe as Heston turns on the culinary magic.
Matt and Heston prepare to reveal their verdicts.
The contestants enjoy their once-in-a-lifetime opportunity.
Heston and the judges makes their deliberations.
A delighted Amina soaks up the pleasure of Heston's company.
Matt stops by Wade's station to check on his challenge progress.
Heston and judges give Kylie's dish the all-important taste test.
Heston Blumenthal joins the judges for a photo op.