To save her friendship with Bon-Bon after "Agent Sweetie Drops" is called back into action, Lyra teams up with her best friend to investigate reports of changelings infiltrating Appleoosa.
This book provides examples of:
- Continuity Nod: Aside from referencing the events of "Slice of Life", it also involves changelings and takes place in Appleoosa.
- Fun with Acronyms: Sweetie Drops works for the agency of S.M.I.L.E — The Secret Monster Intelligence League of Equestria. It also turns out that S.M.I.L.E considers Twilight and her friends to be an unofficial sub-faction of their organization, which they call F.R.O.W.N — Friendship Ranger Organization of Worldwide Neighgotiations.
- The Men in Black: S.M.I.L.E effectively serves as this to Equestria, something hammered in by the cover-art depicting Lyra and Bon-Bon wearing the trademark black suits and sunglasses. Their mission is to keep monsters in check should they get way too dangerous for ponies.
- Shout-Out: To various spy films.
- The title is a shout-out to The Man From Uncle.
- Chapter 3's title, "True Lyra", is a reference to the 1994 Arnold Schwarzenegger action comedy film True Lies, whilst chapter 7's title, "Mares in Black", is obviously one to The Men in Black.
- Ponified versions of various Manhattan landmarks appear in Manehatten.
- The Saddle Hawkins dance is clearly a ponified version of the Sadie Hawkings Dance.