A police officer investigates suspected overdoses that may be homicides and hit close to home.

Thomas' birthday party stirs up memories as tensions with Simon boil over and a new theory emerges.

Mickey and Truman get closer trailing a new lead; a new victim complicates the case.

An ambush leaves Mickey reeling; a Christmas revelation gets Mickey closer to the truth about Kacey.

Mickey faces the consequences of naming Paula; Jimmy Scanlon leads Mickey to surprising places.