| | | | The Present |
| 1 | Patricia | Harney | A detective. Aka: Patti. |
| | Paul | Wizniewski | A police lieutenant. Aka: Wiz. |
| | Daniel Collins | Harney | The chief of detectives. |
| 2 | Amy | Lentini | The assistant state's attorney. |
| | Katherine | Fenton | A detective. Aka: Kate. |
| | William | Harney | A cop. Patti's twin brother. Aka: Billy |
| | | | The Past |
| 3 | Lanny | Soscia | A cop. Aka: Sosh. |
| | Rick | Reynolds | A new detective working with Soscia. |
| | Matt | Crowley | One of the cops. |
| | Brian | Benson | One of the cops. |
| | Brady | Wilson | A film critic who has a TV show. |
| | Michael Xavier | Phelan | An archbishop. |
| 4 | Chocolate Q. | | A rapper. |
| 5 | Ladis | | Former CPD. |
| 6 | John | Barnes | A footballer. |
| | Francis | Delaney | The mayor. |
| | Heidi | Fleiss | Ran an upscale prostitution ring based in Los Angeles. |
| 7 | Michael Leonard | Goldberger | The chief of the Bureau of Internal Affairs. Aka: Goldie. |
| | Ramona | Dillavou | The manager of the brownstone brothel. |
| 9 | Stewart | | Billy's acquaintance. |
| 11 | Kim | Beans | An investigative reporter. |
| 12 | George W. | Bush | 43rd U.S. President. |
| | Richard J. | Daley | Former Mayor of Chicago. |
| 13 | Tristan | Driscoll | The police superintendent. |
| | Margaret | Olson | The Cook County state's attorney. |
| | Kate | Beckinsale | English actress and model. |
| 17 | Bill | Clinton | 42nd U.S. President. |
| | | | The Present |
| 20 | Brendan | | One of Patti's brothers. |
| | Aiden | | One of Patti's brothers. |
| 21 | Mrs. | Ginger | In-charge at the CCD. |
| 22 | Mark | Twain | American writer. |
| 24 | Pameresh | | Billy's doctor. |
| 26 | Jill | Jagoda | Billy's doctor. |
| | | | The Past |
| 31 | Agatha | Christie | An English writer. |
| | Dwight D. | Eisenhower | 34th U.S. President. |
| 43 | Joe | Washington | A sergeant. Aka: Mr. Camel Coat. |
| 45 | Valerie | | Billy's wife. |
| | | | The Present |
| 48 | Chef | Pierre | A British chef. |
| 50 | John | Tedesco | A congressman. |
| | | | The Past |
| 59 | Patricia | Bradford | Divorced mother of three and in her 4th term on city council. |
| 60 | Grace | | Stewart's daughter. |
| 61 | Ann Marie | | Stewart's wife. |
| | Annabelle | | Stewart's granddaughter. |
| | | | The Present |
| 63 | Clarence | Darrow | American lawyer. |
| | | | The Past |
| 67 | Shaw | DeCremer | Once served under the first President Bush's attorney general. |
| 68 | Walter | McCabe | The judge. |
| 69 | | Sanchez | One of the hookers. |
| | Erica | Daniels | One of the hookers. |
| 81 | Ava J. | | One of the hookers. |
| | Marnie B. | | One of the hookers. |
| | Krista K. | | One of the hookers. |
| | Courtney G. | | One of the hookers. |
| | Leann L. | | One of the hookers. |
| | | | The Present |
| 82 | Stilson | Tomita | Billy's lawyer. |
| 86 | Donald | Trump | 45th U.S. President. |
| 87 | Mary Ann | Lentini | Amy's mother. |
| 88 | Ngosi | MacNamara | An assistant state's attorney. |
| | Mark | Madison | An evidence technician for CPD. |
| 89 | Jacqueline C. | Lightford | A forensic scientist. |
| | Loretta | Scopes | Olson's assistant. |
| | Spencer | Lipscomb | A forensic scientist with the Illinois State Police. |
| | | | Past and Present |
| 107 | | | The Present |
| | Estefan | Morales | The County Commissioner. |
