Episode 07: Instinct -

It seems you are referring to a specific episode from the CBS series Instinct . Based on your description of a "solid story" and it being Episode 7, you are likely talking about the installment, titled " After Hours " . In this episode:

The episode heavily involves the overarching "Sleeping Beauty" serial killer storyline, where the killer calls Ryan, showing a personal familiarity. Episode 07: Instinct

Are you watching Season 2, or was this a different show with a similar name? It seems you are referring to a specific

Chipped nail polish found in an alley points to a hotel concierge, revealing a motive involving debt and resentment towards wealthy clients. where the killer calls Ryan

Dylan (played by Alan Cumming) and Lizzie (Bojana Novakovic) go undercover, noted for their strong performances.