The One Chicago Universe has been around for almost a decade, starting with Chicago Fire and ending with its most recent addition, Chicago Justice (lasting only one season). In those ten years, they have become one of the best Chicago shows, giving the fans memorable storylines and relatable characters. One of the best things these characters have done is bond with each other, allowing viewers to see some of the most authentic and loyal friendships on TV.

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From friendships in which one of the characters has seen the other die to coworkers who have been there for each other from the beginning of their career, One Chicago has something for everyone. These friendships will live on even when the shows are over.

Kim Burgess and Kevin Atwater (Chicago P.D.)

Kim Burgess (Marina Squerciati) and Kevin Atwater (LaRoyce Hawkins) on 'Chicago P.D.'

Kim Burgess (Marina Squerciati) and Kevin Atwater (LaRoyce Hawkins) started their journey as police officers together. They were partners in the same patrol car. From the very beginning, they seemed to have a strong connection and shared values. However, their relationship got rocky when Atwater was promoted and became part of the Intelligence Unit before Burgess.

Their friendship stood the test of time and through every challenge they have remained part of each other’s support system. After Burgess adopted Makayla, it was Atwater and his family who helped answer questions the new mom had no answers for. They are a family.

Sharon Goodwin and Daniel Charles (Chicago Med)

Sharon Goodwin (S. Epatha Merkerson) and Daniel Charles (Oliver Platt) on 'Chicago Med.'

Chicago Med made its way into the One Chicago Universe, becoming one of the best medical dramas on TV. With its great storylines and mysterious cases, it brought some fan-favorite characters. Among them are Sharon Goodwin (S. Epatha Merkerson) and Daniel Charles (Oliver Platt) with a friendship that has lasted decades. It is unclear if they were friends before they were coworkers, but they have been there for each other through it all.

Charles was the voice of reason when Goodwin had problems with her children and ex-husband. And Goodwin was there for Charles when he lost his wife and struggled to find his way through mourning. Through thick and thin, these medical experts have remained best friends.

Alvin Olinsky and Hank Voight (Chicago P.D.)

Hank Voight (Jason Beghe) and Alvin Olinsky (Elias Koteas) on 'Chicago P.D.'

Hank Voight (Jason Beghe) seems to be a misunderstood character fans do not know whether to love or hate. The same thing happens on the show, except for one character: Alvin Olinsky (Elias Koteas). Olinsky and Voight knew each other from the beginning of their careers. Even after his time in prison, Hank always had Alvin’s support when the rest of the department seemed to keep him at arm’s length.

Olinsky was the only one who understood Voight to his core and who shared his views and beliefs. They used to work in the same manner, hiding bodies together and doing what was necessary to keep their loved ones safe. That is why Olinsky’s death was hard for Voight who for a while blamed himself for losing his closest friend.

Otis and Joe Cruz (Chicago Fire)

Otis (Yuriy Sardarov) and Joe Cruz (Joe Minoso) on 'Chicago Fire.'

The members of Firehouse 51 pride themselves on being a family. They have each other’s back in and out of burning buildings, and can always count on having a strong support system. However, there are certain friendships that have bonded beyond this sense of family and belonging. One of those bonds is the one shared between Otis (Yuriy Sardarov) and Joe Cruz (Joe Minoso).

RELATED: 10 'Chicago Fire' Episodes That Broke Our HeartsAt first glance, Cruz and Otis do not seem like the kind of individuals who would become friends, but first impressions are not always right. These two become roommates and inseparable, being there for each other through every fire and every breakup. After Otis’s death, Cruz is left devastated and has a hard time moving on from his terrible loss.

Sylvie Brett and Gabriela Dawson (Chicago Fire)

ylvie Brett (Kara Killmer) and Gabriela Dawson (Monica Raymund) on 'Chicago Fire.'

Another one of those special Chicago Fire bonds is the one between Sylvie Brett (Kara Killmer) and Gabriela Dawson (Monica Raymund). Although she was a Candidate of Truck 81, Dawson spends the majority of her time on the show as Paramedic on Ambulance 61. One of the reasons why this worked so well was her friendship to Brett. The two women seemed to understand each other with one simple look, which worked perfectly on the field.

However, after Dawson left the show, Brett pursued a relationship with her ex-husband Matthew Casey (Jesse Spencer), rattling the cage. There were fans who immediately jumped aboard the new ship, but others who refused to accept it. What would this mean for the women’s friendship?

Sharon Goodwin and Maggie Lockwood (Chicago Med)

Sharon Goodwin (S. Epatha Merkerson) and Maggie Lockwood (Marlyne Barrett) on 'Chicago Med.'

Sharon Goodwin is probably one of the most reliable and loyal friends on Chicago Med as her friendship with Maggie Lockwood (Marlyne Barrett) is another one that stands out. This is a career-long friendship in which both women share a profession and a passion. Although Goodwin is now Lockwood’s boss, the friendship remains the same. One in which they feel safe enough to share their experiences and secrets.

Goodwin was the first to know about Lockwood’s biological daughter and the one to support her through her chemotherapy. Lockwood in return has been there for all of Goodwin’s challenges: her divorce, her son’s mingling in the hospital, and her daughter’s pregnancy and surgery. They are always there in times of need.

Matthew Casey and Kelly Severide (Chicago Fire)

Matthew Casey (Jesse Spencer) and Kelly Severide (Taylor Kinney) on 'Chicago Fire.'

Matthew Casey, who returned for the finale of Season 10, and Kelly Severide (Taylor Kinney) are another one of those friendships that thrive beyond Firehouse 51. Sharing more than one cigar on the rooftop of the firehouse and being roommates in times of need, they have shared a brotherhood that goes beyond having similar career paths.

Casey left the show and came back on time for Severide’s wedding because that is what friends do. Now, fans do not know when Casey will return again, but they are sure this friendship will not be forgotten. After all, they have been through hell and back together.

Trudy Platt and Hank Voight (Chicago P.D.)

Trudy Platt (Amy Morton) and Hank Voight (Jason Beghe) on 'Chicago P.D.'

Trudy Platt (Amy Morton) is one of those characters who have little screen time but always ends up stealing the scene with witty comments and emotions. Just like her character, her friendship with Hank Voight is terribly underestimated. They have known each other throughout their entire careers and seem to balance one another out.

The Desk Sergeant is not only an enormous support for the Intelligence Unit, but for Voight himself. She always knows what to do and how to react in situations when others may freeze. In every case, viewers see there is a moment in which he particularly relies on her to get him to where he has to be.

Nadia Decotis and Erin Lindsay (Chicago P.D.)

Nadia Decotis (Stella Maeve) and Erin Lindsay’s (Sophia Bush) on 'Chicago P.D.'

The loss of a character in any form — whether they die or leave — is a terrible loss. For those who were fans of Nadia Decotis (Stella Maeve) and Erin Lindsay’s (Sophia Bush) friendship, the loss was double. The bond between these two women was unexpected but extremely inspirational. Decotis was a prostitute and Lindsay met her on the job, but after that they became the best of friends.

RELATED: Best Unconventional TV FamiliesDecotis moved in with Lindsay and was working towards her degree before becoming a victim of Greg Yates. For Lindsay, the loss was immense, and she spent a lot of time blaming herself. It was Olivia Benson (Mariska Hargitay) who helped her navigate the grief. And even though both characters are now gone, the fans remember their friendship fondly.

Kevin Atwater and Adam Ruzek (Chicago P.D.)

Kevin Atwater (LaRoyce Hawkins) and Ruzek (Patrick Flueger) on 'Chicago P.D.'

Throughout the seasons, Adam Ruzek (Patrick Flueger) has had issues with several characters for his behavior and attitude. It was not until Season 9 that viewers were able to witness his growth and maturity. But through all of his problems and challenges, Atwater has remained a true and loyal friend.

Their friendship is an unexpected one as they seem to have different values, but still it works. When Atwater had problems with his family and needed to keep his siblings safe, Ruzek was there for him. In return, Atwater has been there for every challenge Ruzek has faced regarding his father. Beyond being partners and friends, they are family.

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