Gabriela Dawson and Matthew Casey's relationship didn't last, but Derek Haas and other Chicago Fire showrunners noticed the actors' chemistry early on.

Monica Raymund is best-known for saving lives on "Chicago Fire," but her passion for directing burns just as bright -- especially for one specific franchise.

After six seasons of playing head paramedic Gabby Dawson, "Chicago Fire" star Monica Raymund left the series — but why? "I'm not sure the exact moment when it happened, but I knew that my six-year ...