The Chicago murder rate is on the rise, and amidst the insanity, Diane, Lucca, Maia, and the rest of the law firm find themselves under psychological assault when a client at another firm kills his lawyer for overcharging. Following a copycat murder, the firm begins to look at its own clients suspiciously. Meanwhile, Diane battles with a new partner at the firm, Maia becomes tougher after her parents' scandal puts her on trial, and Lucca is brought back into the orbit of Colin.
An unfortunate event brings the firm together, along with the prospect of a new name partner. Diane struggles to grapple with the insanity of the world, and Maia is confronted with another hurdle in her parents' scandal.
Tensions remain high when the firm learns another Chicago lawyer has been murdered by a client. Liz has her first day at Reddick, Boseman and Lockhart and positions herself as a potential ally for Diane. Maia's trial takes an unwelcome turn when a surprise witness is called to testify against her - and Lucca and Colin go head-to-head in court.
Reddick, Boseman and Lockhart represent a young woman who was assaulted while a contestant on the reality dating show "Chicago Penthouse." Meanwhile, Diane fears she might be the next "Kill All Lawyers" target.
Liz decides to represent her son's favorite teacher after she senses the school fired him for illegitimate reasons. Lucca enlists the help of Elsbeth Tascioni when an unanticipated lawsuit hits close to home. Despite the recent chemical scare, the firm throws a party to celebrate their new offices.
Adrian and Diane serve as outside counsel for a broadcast network planning to air a controversial segment that would derail the career of a beloved male movie star. Maia and Lucca have vastly different experiences while on separate ride-alongs with the Chicago Police Department.
Adrian becomes an overnight celebrity after his candid appearance on a cable news show goes viral. Lucca, who has yet to formally announce her pregnancy, worries about her future at the firm. Meanwhile, Adrian's newfound cable news fame grabs the attention of Chicago's top law firm and the jury of his latest case.
A Democratic National Committee consultant, Ruth Eastman, approaches Reddick, Boseman and Lockhart to develop a confidential impeachment strategy for the DNC against President Trump, leaving the firm's partners at odds. After an impromptu visit from Colin's mom, Lucca is left feeling suspicious of her motives. Maia is intrigued by Ruth's assistant, Carine.
Reddick, Boseman and Lockhart represent an African-American undercover cop, Rashid Clarkson, who was left crippled after being shot by another Chicago police officer in the line of duty. The case's opposing counsel is legend Solomon Waltzer, whose tactics have the firm questioning the legitimacy of his evidence. Diane finds herself at a crossroads with both Kurt and Tully.
A Russian student asks Diane to protect her from deportation, claiming she was one of the women filmed with President Trump in the alleged "Golden Shower" tape. Meanwhile, Maia and Lucca suggest an unconventional lawyer to represent Jay's friend Craig Savador at his upcoming appeal and Colin meets with the Cook County Democratic Committee.
Reddick, Boseman and Lockhart is left in disarray after a partner at the firm becomes the latest "Kill All Lawyers" victim by an unknown assailant. The Chicago police chief causes a stir when he goes after the firm's high profile clients Lemond Bishop and Colin Sweeney as potential suspects. Amidst the chaos, Colin is reminded of his true feelings for Lucca.
Heated debates occur at the firm when Liz and Maia represent a well-known photographer, Ron Williams, suing a woman who provided an account of their relationship to a website. Jay continues to investigate possible suspects in Adrian’s shooting while Diane receives surprising news from her accountant.
While on his way to court with Maia and a witness, Jay is being arrested by the police. When Diana and Liz rush to help him out, they discover that it is an immigration issue and federal agents are about to deport him. Meanwhile, Adrian goes back to work.
The FBI question Diane as part of a job background check on Kurt, leading to unexpected and serious consequences. The mayor of Chicago invites Adrian and Julius to join a 'think tank' tasked with figuring out how to spend funds that will address the "Kill All Lawyers" problem. Chaos ensues in the delivery room after Lucca goes into labor early.