AN INCIDENT AT A SORORITY PARTY 30 YEARS AGO LEADS TO A DOUBLE MURDER Harold and Joyce Foley (guest stars Stephen Kunken and Erin Dilly), both well-known biologists at a local university, come home to find their young son Eric (guest star Timothee Chalamet) and the housekeeper brutally murdered. Detectives Lupo (Jeremy Sisto) and Bernard (Anthony Anderson) believe that the Foley's work on a controversial pharmaceutical study made them targets for the killer. Ned Lasky (guest star Matt Malloy), a reporter for Science Today who may have some serious emotional issues, has also been harassing the Foley's. Lupo and Bernard take Joyce on a trip down memory lane to a sorority party 30 years ago to find some answers. With very little evidence to work with, A.D.A's Michael Cutter (Linus Roache) and Connie Rubirosa (Alana de la Garza) work diligently to track down a key witness who was there.