You Never Know Who's Who
S3 episode 6 Aired on October 28, 2015

The discovery of a dead body jumpstarts an investigation in operatives who believe they are part of a covert CIA operation. - A suspicious person call turns into a murder investigation when Burgess (Marina Squerciati) and her temporary partner Price (guest star Travis A. Knight) discover the body of a dead man in an SUV. After Mouse (guest star Samuel Hunt) identifies the victim as the owner of a security company, the unit soon realizes there might be more to his story. Meanwhile, Roman (Brian Geraghty) takes Andrew (guest star Vincent Shuster) out for a memorable daytrip and Platt (Amy Morton) offers Ruzek (Patrick Flueger) some assistance. Halstead (Jesse Lee Soffer) and Lindsay (Sophia Bush) take a step forward in their relationship. Jason Beghe, Jon Seda, Elias Koteas, LaRoyce Hawkins also star. Oliver Platt, Nick Gehlfuss, Madison McLaughlin and Barbara Eve Harris guest star.