Raimy and Satch discover a shocking connection to the Nightingale's first kill. When Raimy shares this news with Frank, he works to dig up additional information. Meanwhile, Frank and Julie are forced to have an honest conversation, and Raimy has a surprise visitor.

A female police detective in 2016 discovers she is able to speak via a ham radio with her father (also a detective) who died in 1996. They forge a new relationship while working together on an unresolved murder case, but unintended consequences of the ‘butterfly effect' wreak havoc in the present day.