The mysteries of “Chicago P.D.” will soon be solved when the show returns on Jan. 3 on NBC. Tons of questions will also be answered about the revelations on the upcoming Season 4 including Lindsay’s father. What excites fans more is the upcoming crossover with “Chicago Fire.”

In the last episode, the show left us with Anthony Dawson leaving Chicago’s police department. His new job now is the lead investigator at the State Attorney’s Office. But despite Lawson’s leave, another officer will join the troop. As Voight (Jason Beghe) offers Kim Burgess (Marina Squerciati) her dream job to have a spot in the Intelligence Unit. The patrol officer indeed deserves her promotion.

Speaking of spoilers, Christian Times stated that the Season 4, Episode 9 “Don’t Bury the Case” features firefighter Kelly Severide (Taylor Kinney). The firefighter was accused of a hit and run case caused by his car. He would then need Voight’s troop to lift the case of the accused crime including Lindsay. Voight’s team then discovers a group of car-jackers that may prove Severide’s innocence.

Meanwhile, Detective Erin Lindsay (Sophia Bush) will uncover the biggest mystery of her life according to IBTimes. As she will face her long lost dad, Jimmy Sanguinetti (Guest star, Tony Crane). Their meeting would be an unexpected one since her mother told her that his father has always been imprisoned in jail. But the shocking truth is, he isn’t. Jimmy will then tell her that the reason he wasn’t approaching Lindsay is that during those 10 lost years, he already got married and is fathering two sons.

Despite the revelation about her father, Lindsay then crosses with former boyfriend, Kelly Severide wherein they agree that they should have a double date since they already have both new lovers.

In addition, Spoilers Guide stated that Season 4, Episode 10 entitled “Don’t read the news” confirms that the Chicago P.D. same as past crimes, has another serial killer case on their hands.

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