The Flynn-Fletcher family are in England to visit Lawrence's parents, Reginald and Winifred. While there Phineas and Ferb decides to hold a medieval tournament after hearing a story about the Black Knight.
Meanwhile Agent P is sent to infiltrate EvilCon to spy on Dr. Doofenshmirtz.
This episode marks the introduction of Lawrence's parents.
- Downer Ending: In-universe, the Black Knight's quest to slay the dragon ended poorly.
- Hey, Wait!: Doofenshmirtz confronts an undercover Perry...because he just so happens to be impersonating Doofs personal hero.
- Suspiciously Specific Denial: Perry's ID for going undercover at EvilCon reads "Note: Not a platypus."
- You Say Tomato: The background singers during Ballad of the Black Knight quibble about the pronunciation of Worcestershire.