Chicago Fire Season 4 Episode 13 Promotional Photos.<br>Chicago Fire 4x13 Promotional Photos.<br>Chicago Fire 4x13 The Sky Is Falling - The firehouse is on high alert when mysterious threats begin to emerge throughout Chicago. The situation turns dire .<br>Chicago Fire 4x13 Promo Photos The Sky Is Falling Official website: Official Twitter page: <br>Chicago Fire 4x13 The Sky Is Falling -4x1 Mysterious threats begin to emerge throughout Chicago and the situation gets worse when news of a mass shooting .
