The penultimate heat week begins, as five more amateur cooks battle against each other.
First, they must hold their nerve in the infamous Invention Test, where they have just one hour to cook an exceptional dish from scratch.
They must then survive the extremely tricky Palate Test, a brand new MasterChef challenge which sees John demonstrate a chicken pot pie with coleslaw. Without seeing the demo, the amateurs are given just a few minutes to taste this dish before being asked to write down exactly what is in it, using their sense of smell and palate. Then they are asked to recreate John's dish in just one hour - without a recipe.
At the end of these two challenges, for two contestants it is the end of the road. The remaining three are then thrown into a busy lunchtime service in London's Bistro 51 and, after just an hour of learning the ropes, the home-cooks are set loose to prepare dishes for paying customers.
Finally, it's back to the MasterChef kitchen for the final test of tonight's Heat show - cooking their own two brilliant courses to impress John and Gregg. The contestants must draw on all their skills and influences as they prepare this food, because it is their last chance to win a place in the quarter-finals.
Only the best will survive, taking their first step towards being crowned MasterChef Champion 2013.