In the first quarter-final, the most talented six of the week return to compete for a place in Knockout Week.The competitors take on an intense challenge set by formidable food critic William Sitwell, who calls for an exquisite plate of food based on infamous school dinners. This is not a time for lumpy mash, overcooked fish or gloopy gravy. William doesn't carry fond memories of what his school served up, so he's praying for some originality and humour.Those who come out with poor grades will be on the next bus home, as only the best head into Knockout Week.