Chicago PD 4×21 “Fagin” Season 4 Episode 21 Promo – When the team is called to an in-progress bank robbery, they come across Detective Hailey Upton (guest star Tracy Spiridakos) trying to take over the crime scene with her Robbery-Homicide unit – butting heads with Voight (Jason Beghe) in the process. As the robberies continue to be executed around the city, Lindsay (Sophia Bush) is forced to make a decision in the heat of the moment, revealing a surprising suspect behind the mask. While working on the case at the district, Upton is shocked to come across Platt (Amy Morton), who has a special connection to her past. Also starring Jesse Lee Soffer, Patrick John Flueger, Elias Koteas, Marina Squerciati and LaRoyce Hawkins. Guest starring Carl Weathers, Monica Raymund and Esai Morales.