The 16 new contestants face their first QuickFire and Elimination rounds using themes from Chicago's regional cuisine.

A farmers' market takes prominence in this week's QuickFire, and an exotic location is the setting for the Elimination round as the remaining chefs cook for guest judge Wylie Dufresne.

The contestants mix it up with Rick Bayless while creating a fiesta for a community.

The remaining chefs demonstrate their aptitude with knives, and then help Richard Roeper throw a film-themed dinner. Daniel Boulud guest judges.

The dreaded taste test is back, and even before the chefs recover from it they must cater a charity event. Ming Tsai Guest Judges this week.

Simple pleasures is the theme for tonight's round as the chefs must create a dish that complements beer, and then throw a tailgate extravaganza for fans of the local team.

The chefs begin with a sugary challenge, and then move to the historic Second City Theatre where their improvisational skills will be tested by masters of the art – one of the resident troupes. Johnny Iuzzini from Jean Georges restaurant guest judges.

The microwaves are back, and this time the contestants are to make a healthy meal using a single main ingredient. Chef Art Smith, owner of Table 52 in Chicago performs guest judge duties.

The remaining chefs' knife skills are challenged again, followed by a wedding reception challenge which might bring the blades out for an entirely different purpose.

Salad, one of the least respected dishes by chefs, takes center stage tonight as the contestants are challenged to reformulate it, then they continue with the healthy kick by trimming calories and all things bad from a classic entrée.

It's all about service tonight as the chefs work the line during a breakfast rush at a diner, and then create their own restaurants from scratch. Washington, D.C. Chef and restaurant owner José Andrés guest judges.

The remaining chefs' butcher skills are tested, and then they must use the cut of meat they made. Guest judge Rick Tramonto, a Chicago chef and restaurant entrepreneur.

There are four chefs and only three spots for the final round, and the contestants know it as they travel to Puerto Rico for the next two challenges.

The finalists cook "the most important meal of their lives" for the judges to determine which will be crowned Top Chef.

Season four cast and judges gather to reminisce and learn the winner of the fan favorite contest.