During a baseball game, Verne meets a friendly new kid named Chris, who turns out to be a whiz at the sport. While at the comic book store together, they get an old poster for a defunct circus and use the DeLorean to catch the show in its heydey, accidentally bringing Marty along for the ride. But while in the past, Verne discovers Chris has been keeping something under her hat. Will the new friendship survive?
This episode includes examples of the following tropes:
- Big Brother Mentor: Marty serves as the older voice of reason when Verne rejects Chris for being a girl and tells him he'd better loosen up if he doesn't want to lose a good friendship.
- Circus Brat: Verne comments that he never intends to run away to join the circus after the two end up pressed into service for increasing the owners' debt to Farmer Mac Tannen.
- Foreshadowing: Chris being a girl gets hinted at multiple times before it actually comes out.
- While they're looking at the circus poster, Chris gushes about potentially getting a glow-in-the-dark necklace. She switches to talking about swords after getting a funny look from Verne.
- When Marty asks if anyone has a paper clip to help fix the DeLorean, Chris offers a bobby pin.
- Girls Have Cooties: When Marty doesn't see what Verne's problem is with Chris being a girl, Verne protests that the kind of interaction he had before learning her gender involves "major cooties."
- Good News, Bad News: After accidentally volunteering as a human cannonball and landing on the DeLorean, Marty tells the kids that there's good news and bad news. The bad news is, the carburetor is cracked. The good news is, the damage still isn't as bad as the lackluster circus performance they just saw.
- Immediate Self-Contradiction: When Chris asks if Doc will mind that they took his car, Verne casually says his dad lets him drive all the time. When Marty, who was in the backseat hunting for a paper clip, puts a hand on his shoulder, Verne immediately freaks out and begins apologizing.
- Running Gag: Marty keeps offending the bearded lady by addressing her as a guy and suffering her wrath.
- Sweet Polly Oliver: Chris pretends to be a boy so she can hang out with the girl-hating Verne. Verne doesn't react well when he learns the truth, but he lightens up by the end of the episode.
- Tomboy with a Girly Streak: Chris likes playing baseball and knows something about car parts. However, she prefers glow-in-the-dark necklaces over fake swords as souvenirs.
- Women Drivers: When Chris crashes the DeLorean into a fence, Verne tells Chris that Chris drives like a girl. Meaningfully, Chris takes deep offense to the insult.
