Depending on which show you are referring to, here are the most relevant "papers" or guides:

Entertainment Weekly provides a recap of "Mr. Kaplan: Conclusion," which centers on the "truth" Red is hiding. Other Notable S4E21 Episodes

Season 4, Episode 21 is It features a major resignation and a high-stakes investigation.

: "Asylum" (Part 1 of the S4 finale). You can find technical and plot discussions on Wikipedia .

Season 4, Episode 21 is titled While not titled "The Last Word," it is famous for Captain Picard’s concluding monologue about freedom and vigilance.

A comprehensive breakdown of the episode's intricate plot and political fallout is available at Keg of Glory . The Blacklist