The time has come, for someone other than Ash to win his last gym badge. Now Ash and co. arrive at Humilau City (after they end up walking in seperate directions). From there, they meet Marlon, the gym leader of the Humilau City Gym after a big surprise when he's riding on his Wailord. Now that they're here, Cameron is ready for a Gym battle for his eighth badge. Will he win without Riolu's help? Yes.
The title of the episode is a parody of the movie "The Road to El Dorado".