It Came from the Nightosphere

After Finn agrees to help Marceline record one of her musical compositions, she begins to sing "The Fry Song"—a tune about the rift between herself and her father, Hunson Abadeer.[lower-alpha 4] Finn, feeling sorry for her, decides to summon her father from the hellish Nightosphere, failing to realize that her father is the domain's dark leader and that he consumes souls. He materializes before Marceline and Finn, attempts to kill Finn by devouring his soul, and successfully steals Marceline's axe bass. Finn and Marceline give chase.

Marceline's father moves throughout Ooo, consuming the souls of all living creatures that he can find. Finn and Marceline first try to crush him with a rock, but the resulting skirmish between father and daughter merely infuriates Hunson Abadeer. He assumes that Marceline is trying to kill him to take over the Nightosphere, but she merely wants her bass guitar back.

Finn and Marceline attempt one last time to stop Hunson Abadeer, who has now grown huge. Due to his size, Finn is easily defeated. Marceline, infuriated by her father's lack of understanding, storms off. Finn, in a last-ditch effort to save the day, plays back the recording of "The Fry Song". Suddenly, Marceline's father understands why she is upset, and the two reconnect. Finn uses this beat as an opportunity to cut all of the souls free from Hunson Abadeer's "soul sack" before banishing him back to the Nightosphere.

"It Came from the Nightosphere" first aired on Cartoon Network on October 11, 2010. The episode was viewed by 2.001 million viewers and scored a Nielsen rating of 1.3/2 percent. This means it was seen by 1.3 percent of all households and 2 percent of all households watching television at the time of the episode's airing.[19] This marked a decline from the first season premiere, which had been viewed by 2.5 million viewers, but it marked an increase from the first season finale, which was watched by only 1.77 million viewers.[20][21] "It Came from the Nightosphere" also marked gains when compared to the same timeslot a year prior; for instance, 732,000 kids aged 6–11 watched the episode, an increase by 35 percent when compared to the previous year.[22]

"It Came from the Nightosphere" was highly praised by critics. Tyler Foster of DVD Talk called it "a pretty decent example of all the notes the show can hit."[23] He was particularly pleased with the way "the rift between Marceline and her dad is handled with a nice seriousness that fits right in alongside absurd gags about penguins".[23] He also noted that "any episode that includes a song is a plus in my book."[23] It was also called the "real highlight" of the eponymous DVD release by Charles Webb of MTV Geek.[24] IGN writer Matt Fowler later referred to the episode as a "classic".[25] In a separate review, he later wrote that the episode "has come to represent the best of Adventure Time, and Marceline's [sic], with her angst-y anti-daddy song and her Freddy Krueger-esque sweater has launched a thousand cosplays."[26] Writers of Spin ranked "The Fry Song" as the forty-fourth best original song performed by fictional characters in any medium. James Grebey called its subject matter deep and from a place of uncontrolled emotion, and characterized it as mature but also eccentric.[27]

Ward was very happy with the episode. He complimented storyboard artists Muto and Sugar, saying that the former "has a hilarious slapstick set-up-the-punchline kind of style of comedy" and the latter "is amazing at executing these super romantic, emotional goosebump-kind of feelings".[25] He was particularly pleased with the ending, noting that "I love that goose-bumps feeling in a climactic scene with music rising. In that episode you're talking about, there is that rising action toward the end, and then LSP […] cuts in and says 'drama bomb!' in the middle of it to sort of, like, cut its legs out. Which I think is a lot of fun."[28]

"It Came from the Nightosphere" was later nominated for a 2011 Primetime Emmy Award for Outstanding Short-format Animated Program, although it did not win.[29]

• "It Came from the Nightosphere" at IMDb