Marceline’s tragic past is one of the most heartbreaking elements of Adventure Time, and “Ketchup” is an episode that explores Marceline’s difficulty coming to terms with the pain and loss she’s endured during her life. When BMO arrives at Marceline’s house to hunt down vampires (not realizing that they were all defeated back during the Stakes miniseries), the two of them have a catch-up session to pass the time while BMO recovers data from an ancient USB drive. They tell each other stories that are increasingly emotional, and by the end, Marceline has a major moment when she realizes that there are some memories of her past that are too meaningful to keep locked away.

I was just saying yesterday that my favorite thing about Adventure Time is seeing how different creative voices change the series, and “Ketchup” is a great example of this, welcoming guest animators Lindsay and Alex Small-Butera for three sequences that each have a different animation style. The first sequence has BMO telling Marceline about his recent ocean voyage with Finn and Jake in the Islands miniseries, and it’s an ethereal, dreamlike reinterpretation of events depicted with fluid visuals and a sunny color palette. It’s not what actually happened during Islands, but as BMO says later, he’s more concerned with the emotional truth of the journey. The animation reflects that with its vibrancy, and there’s a sense of exhilaration in the storyboarding that captures BMO’s excitement during his trip.

Marceline puts on a puppet show for BMO when she tells her story about Lollipop Girl and her friend, Rock Star Girl, whose relationship falls apart when they are infected with a virus that turns them into potatoes. The animation for this sequence has a simplified design sensibility that evokes the look of puppetry without being limited to puppet characters, and it’s easy to see this segment translated into stop motion animation because it has a more tactile quality than the one before it.

Marceline doesn’t give her story a satisfying ending because she doesn’t want to engage with ideas that require her to be emotionally vulnerable, suggesting that her sequence has deeper resonance. This tale of two friends being pushed apart by personal change has me wondering if it might be a glimpse into why Marceline and Princess Bubblegum’s romantic relationship dissolved in the past, and while the show hasn’t explicitly delved into their time as girlfriends, we do have confirmation that they were an item. The major theme for Marceline this week is her reluctance to look back at relationships that took a turn for the worse, and while I may be overanalyzing Marceline’s story, there’s no denying this theme when we get to the last narrative of the episode.

“Ketchup” is an episode that misdirects the viewer for most of its runtime, making them think that this is going to be a light story about BMO and Marceline entertaining each other. But in the final minutes, it becomes something much more substantial. After the data recovery is complete, BMO projects the contents of the USB drive on the wall, revealing a collection of pictures that ends with Marceline as a child, playing on the beach with her mother. That shot alone is brimming with emotion because we know the tragedy of Marceline’s past, but that’s just the teaser for the gut punch that follows when Marceline asks BMO to tell her a story about the little girl and the nice lady in the picture.

This final story from BMO has the biggest stylistic shift, with a flat aesthetic that makes the animation look like moving paper cutouts. It has a children’s book quality, which works very well considering it explores a blissful childhood memory. I’ve always been a person that doesn’t like stopping what I’m doing to take a picture, but as I’ve gotten older, I’ve come to appreciate the value of having a snapshot of a moment that won’t fade like my memory. When people leave your life, those photos become a tether to the time you shared with them, and upon seeing the image of her mother, Marceline is overwhelmed with feeling that she can’t ignore.

“Ketchup” highlights the versatility of its guest animators and shows hows embracing different styles can enrich storytelling. Having this range of animation aesthetics makes this a more fulfilling episode, and even if it didn’t have that emotional climax at the end, it would still be a compelling chapter because of how it plays around with the medium.

Stray observations

• There are lots of fun little songs in this episode, starting with Marceline’s tune about playing bass in her face. They don’t play an especially big role in the emotional storytelling, but they do provide some light musical humor.
  
• I’m kind of sad we never got an episode about BMO, Vampire Hunter.
  
• Regular Show’s J.G. Quintel has a quick cameo in this episode as the voice of a bluebird that appears in BMO’s story. Coincidentally, there’s an Adventure Time/Regular Show crossover comic debuting from Boom! Studios next month!
  
• “I also hunt data recovery!”
  
• “I wanna ride on a boat boat boat/I wanna ride on a goat goat goat/Middle C’s my favorite note note note/I’m on a cat that float float floats”
  
• BMO: “The ending was not believable.” Marceline: “Come on, you had a cat with legs on its back.” BMO: “I was being emotionally truthful.”