Return to the Nightosphere

"Return to the Nightosphere" is the fifth episode in the fourth season of Adventure Time.

Synopsis
Marceline’s dad locks up Finn and Jake in a prison in the Nightosphere, and they can't remember why. Now, they must find a way to escape the Nightosphere. Part 1 of the two-part episode.

Plot
The episode starts with Finn and Jake waking up in a pile of bananas in a jail cell with their memories completely lost. They find out that they are in the Nightosphere when their jail guard tells them where they are and after asking how they can get home, he explains that they can't unless "he" allows them. Then they, along with other demons, are set free because they cannot leave anyway. They climb up through a hole and look around to get a good view of the Nightosphere, after that they ask for help from a Half Monster Demon who tells them to climb into him and he will carry them to the Teller.

After being dropped off at a river full of demons, a traveler explains to them that they have to wait in a line. They spend almost 28 days waiting for their turn to see the Teller. When it is finally their turn, they have to stand in another long line. In that moment, the Nightosphere ruler appears in a mist and starts killing all the demons that were there to ask him questions, so Jake and Finn hide behind a rock. They barely escape, and follow the ruler to its castle. There, they fight their way back to the portal in order to get home.

They go into the portal and the ruler follows them. Finn fights it and cut its head with his Demon Sword, which reveals that the ruler was really Marceline all along. When they get back to Ooo, Marceline closes the Nightosphere portal and tells them to never come back. Finn claims they must go back to discover the truth.

This episode continues with its second part: "Daddy's Little Monster."

Main characters

 * Finn
 * Jake
 * Marceline

Minor characters

 * Demons
 * Ab Demon
 * Big Demon
 * Boat Demon
 * Half Monster Demon
 * Hunson Abadeer
 * Nightosphere Jailer
 * The Teller
 * Snail

Mentioned and pictured

 * Peppermint Butler (pictured)
 * Abraham Lincoln (pictured)
 * Elder Toad (mentioned)
 * BMO (mentioned)

Trivia

 * It is revealed in this episode that Marceline's dad has an actual name, Hunson Abadeer. Throughout the episode, Finn and Jake refer to him as "Hunson."
 * Abraham Lincoln can be seen with the Lord of Evil in a picture, this being the first time Abe is shown in the actual series.
 * Another picture shows Marceline as a child standing next to her father on the left and another woman standing in the right who has a striking resemblance to Marceline. This may be her mother.
 * In one of the pictures, Peppermint Butler is seen playing golf with the Lord of Evil.
 * The presentation of the Nightosphere was similar to the Land of the Dead in the episode "Death in Bloom." Also, the song played when F&J entered the Half Monster Demon, were the same played during the same scene of the presentation of the Land of the Dead.
 * Jake spoke in Japanese in this episode - albeit broken. After cheering up Finn, he said "‘(上手で頑張ってね）Jouzu de Ganbatte ne" - which roughly translates as "Being that you are skilled you can do it!."
 * On a cupboard in Abadeer's kitchen there were several badges with American states names on them.
 * Even though Hunson’s last name is Abadeer, some demons mispronounce it, saying "Aberdeer."
 * Finn and Jake were in the Nightosphere for thirteen days.
 * John DiMaggio (the voice of Jake) performs the voice of the Teller in this episode.

Cultural references

 * The appearance of The Nightosphere and its denizens appear to be directly inspired by the paintings of 16th century artist Hieronymus Bosch. Particularly the third panel of his triptych painting "The Garden of Earthly Delights."
 * During the first recording of the Nightosphere, a creature floats by that looks similar to a Ghast from the sandbox game Minecraft.
 * As the "blood mist cloud" retracts into the tower after attacking the line, a clinking sound can be heard, reminiscent of the sound heard as the smoke monster on "Lost" retreats.
 * Jake records their activities on his new cell phone and uses the video to discover what had happened after they lost their memory, possibly referring to the movie The Hangover, which has a similar plot.
 * The boat demon rowing over the other demons' heads is similar to the demon Phleygas, in Dante Allighieri's poem Inferno, who ferries over the river Styx, which is filled with wrathful and sullen sinners.

Episode connections

 * The hair style that Marceline wears is the same as in "It Came From the Nightosphere," which is coincidental because Marceline's father was in both episodes.

Production notes

 * This episode was previously titled "They Went to the Nightosphere," and was renamed. Some sites such as T.V. Guide still used the old title. The current title was used as a former title for the episode "It Came from the Nightosphere."
 * This is part one of a two-part episode, and originally aired together with "Daddy's Little Monster."

Storyline analysis
TVideos Adventure Time - They Went to the Nightosphere (short preview)|Short Preview Adventure Time - They Went to the Nightosphere (long preview)|Long Preview Return to the Nightosphere Daddy's Little Monster - Long Preview 2|Another Long Preview "They Went to the Nightosphere|Animatic
 * It is obvious that the Nightosphere ruler is actually Marceline as her demonic head is noticably smaller than her father's.