While officially the 17th episode of Season 4, "Requiem" is a pivotal origin story often grouped with mid-season highlights. It focuses on the backstory of (Kathryn Nemec) and her history with Katarina Rostova and Masha (Liz).
(Season 7, Episode 22 / Sometimes confused with S4) [S4E8] Requiem
: This detailed article from Pop Culture References explores how the episode serves as a major clue to Reddington's true identity, showing Kathryn's life as Liz's nanny and her initial bond with Katarina. While officially the 17th episode of Season 4,