When he opened his Chicago restaurant, Alinea, in 2005, the modernist chef Grant Achatz redefined the restaurant experience by challenging some very basic conventions of dining. He asked, Why does food have to be just one temperature? It doesn't, he replied, serving a soup called Hot Potato/Cold Potato. He asked, Why do you have to eat with a fork? You don't, he declared, creating custom-built devices for specific recipes. His fascination with visual surprise and the power of scent makes for thrilling sensory experiences at Alinea, The Aviary cocktail bar and Next, which sells tickets to themed dinners.