Mr. Packenham takes the 4th grade class on a field trip to see the opera "Carmen", and while Arnold falls asleep and dreams of him and Ruth, Helga dreams of getting rid of Ruth and having "Don Arnold" for herself.
The kids are at a field trip to the Civic Opera. Unfortunately, most of the kids (especially Helga, Gerald and Harold) are not enthused about it. Mr. Packenham nevertheless tries his best to make "opera-lovers" out of the class as he points out songs from famous operas such as Ride of the Valkryies and Pagliacci. He then announces that the opera they will be seeing is Carmen, a well-known opera that tells the tragic love story of military officer Don Jose and the beautiful "gypsy" Carmen, who is pitting the former with the famous bullfighter Escamillo for her affections. After hearing about the heroine Carmen, Helga seems a little more interested about it as the class heads to the auditorium.
As the opera's overture plays, Arnold drifts off in another one of his vivid dreams: Arnold stands on a stage and sees Gerald dressed as Figaro singing the character's name and disappears as fast as he shows up; Harold appears dressed as the crying clown Pagliacci and runs away to the setting of Spain in the 1820’s.
Arnold (now playing as Officer Don Arnold) sees a seductive Ruth (as Ruth McCarmen) and is encouraged by the other kids (as extras) to ask Ruth for a dance, only to be snapped out of the dream by a spitball shot by Helga. Arnold is then told that he has slept through the First Act while Gerald is trying to find music to listen to while waiting for the opera to be over.
Phoebe then explains the Second Act where Don Jose is convinced by Carmen to defect from the military to join her band of smugglers. While Phoebe explains the sudden conflict with Escamillo, Helga herself falls asleep and has her own dream similar to Arnold's: Helga then takes the appearance of a Valkyrie and shouts at Don Arnold asking why would he choose Ruth over her. She then uses her "Golden Magic Slingshot" to shoot the trap door beneath Ruth to "destroy" her. While Don Arnold searches for a missing Ruth, Helga undergoes a quick costume change into the beautiful Carmhelga. However, Don Arnold goes with it and agrees to join her band of gypsy smugglers.
As Carmhelga asks what could possibly be better than this, Curly then makes his appearance as the toreador Curlymillo, attempting to win Carmhelga’s heart (and nearly succeeds). Suddenly, an infuriated Don Arnold challenges Curlymillo to a "sword fight."
Eventually, Don Arnold defeats Curlymillo and earns Carmhelga's love. As two are about to kiss, a massive quake erupts that panics the entire cast. Don Arnold then runs away as Carmhelga calls out to her true love as the backdrops collapses and the curtain goes down.
Helga then wakes up from her dream as she realized she slept through nearly the entire show. Gerald asks Arnold his thoughts on Carmen, only for Arnold to say it was interesting as Ruth walks across them. Phoebe then asks Helga the same, and Helga's answer was that it was "okay."
As everyone exits the auditorium she then says to herself: "It just ended too soon." and she sighs lovingly.