The final moments of "Chicago Fire" season three were dramatic and sensational, to say the least. Dawson went to Casey's apartment in order to tell him about her pregnancy results but instead found a murdered stripper named Katya lying on the floor and a disappeared Casey. Is Dawson pregnant? More importantly, where is Casey?

Season four promises to answer these questions when it returns to the small screen this fall. While speculations are rife about Casey's fate, "Chicago Fire" executive producer Matt Olmstead spoke to TVLine in an interview, providing some much-needed hints and spoilers for the upcoming season.

When asked about Katya's murder, Olmstead cleared the air that Katya was not in Casey's apartment for personal reasons. While the two flirted in season three, the executive producer made it clear that Casey and Katya were never meant to have a full-blown affair.

Gabby's pregnancy changes things for the ace firefighter. For starters, she most assuredly cannot continue her current role. When asked about pregnant firefighters' policy in Firehouse 51, Olmstead replied, "They'll fall back to Ambo. The alternative is getting a desk job in the fire department while you're still pregnant. So of the many things she's dealing with is the fact that she'd have to be reassigned off the truck."

Many seasoned viewers may believe that Dawson's pregnancy sparks hope that she and Casey may get back together. However, the producer was quick to point out that Dawson is not thinking about getting back together with her former flame. Instead, she is concentrating on how to deal with her pregnancy. Moreover, if Casey finds out she is pregnant he will downplay his shock and be protective.

Olmstead also teased the addition of a new character on the truck, for whom casting is taking place. Meanwhile, another TVLine report speculates that Casey may have ran because he was afraid of getting framed for Katya's murder or Jack Nesbitt found out about his undercover role and kidnapped him.

"Chicago Fire" airs on Oct. 13, 2015 on NBC.