4x21 - Masterchef

Three previous contestants return for another shot at the title. But they've been here before, so this time things are tougher: they have to survive an 18-hour shift in a professional kitchen. First they are off to City Café for breakfast service, and then it's straight to Simpsons in the Strand for evening service. Who has the endurance and the skill to make it? Only the best will go through to the quarter final.