Mortal Recoil

"Mortal Recoil" is the twenty-fifth episode in season two of Adventure Time. This is half of the two-part season finale, along with "Mortal Folly".

Synopsis
Though the Lich appears stopped, an idiotic accident by the Ice King has lead to Princess Bubblegum becoming altered, leading to an unlikely final showdown with one of the greatest evils in order to save all life in Ooo.

Plot
In the previous episode, Princess Bubblegum was dropped into The Lich King's Well of Power, which had melted her body. Dr. Ice Cream and Nurse Poundcake, along with other candy hospital staff, save Princess Bubblegum's life, but she is still very ill and is confined to her room, with Finn and Jake acting as her caregivers. However, she exhibits strange behavioral problems including spasms, heavy breathing, convulsions and crawling into the bathroom. Finn returns her to her bed and takes some time to confide his feelings to her, asking Jake to leave the room. Finn thanks her for the sweater she made him and tells her that they should discuss their feelings later, but she is unresponsive. Princess Bubblegum then asks Finn to bring her several things, left unknown to the audience. When Jake returns, he tries to play some music for Princess Bubblegum, but PB summons magical fire into the room and scares Jake out of the room. When Finn returns to the hall outside, he is holding an assortment of items, which he reveals are things like gasoline, turpentine, plutonium and other hazardous chemicals. Jake urges Finn to not bring the chemicals to Princess Bubblegum, but she opens the door and takes them from Finn and returns to her room.

Jake then tells Finn of the fire she summoned, which alarms Finn. The two enter the room where Finn believes PB is just having private time in the bathroom. Jake looks through the keyhole and forces a relunctant Finn to as well. They see Princess Bubblegum, now with a demonic form, pouring the chemicals into her bathtub, forming a pool like the Lich's Well of Power. When she starts drinking the liquid, Finn and Jake try to stop her, but she rips the tub off of the floor and drinks the entire concotion, growing as tall as her tower. As she begins to attack the Candy Kingdom, Ice King appears and explains that he saw the Lich possess Princess Bubblegum with his Wizard Vision. He wants to help Finn and Jake, but Finn angrily refuses his assistance, as it was his fault the Lich escaped to his lair and posessed Princess Bubblegum in the first place. Finn tries to defeat the posessed Princess Bubblegum with the sweater she gave him, but fails. Finally, he accepts Ice King's help. As Finn distracts PB, the Ice King freezes her from the feet up. The Candy Kingdom rejoices, but their jubilance turns to shock when Princess Bubblegum falls over and shatters. Dr. Ice Cream, Nurse Poundcake, and Doctor Princess attempt to reassemble Princess Bubblegum, but run out of pieces. She then reveals to everyone that while Princess Bubblegum is alive, her body is now only thirteen years old. Finn remarks that he is thirteen as well, PB calls Finn a hero and he and Princess Bubblegum share a loving embrace. As everyone celebrates, the Snail who freed the Lich is seen waving menacingly in the background, with eyes that glow like the Lich's, which shows that the Lich might return.

Major Characters

 * Finn
 * Jake
 * Princess Bubblegum
 * The Lich
 * Ice King

Minor Characters

 * Peppermint Butler
 * Raggedy Princess
 * Dr. Ice Cream
 * Nurse Poundcake
 * Doctor Princess
 * Candy People
 * Cinnamon Bun
 * Emerald Princess
 * Wildberry Princess
 * Lumpy Space Princess
 * Guardians of the Royal Promise
 * Snail

Music

 * Not Feelin' Good Song

Trivia

 * This episode and "Mortal Folly" would have been the final episodes of the season prior to the rescheduling of "Heat Signature". The two-part episode is still considered the season two finale by the show's crew.
 * This is the first time Finn directly states he's 13 years old, although this was already known from the events of "Mystery Train" and from statements made by the show's crew.
 * This is the first time the Snail is shown in the titlecard and/or in the final shot of the episode.
 * Young Princess Bubblegum was voiced by Isabella Acres.
 * In the emergency room at the start of the episode, the heart monitor screen is displaying the first 15 digits of pi.
 * When PB was possessed by The Lich, she spoke with a deeper voice, her skin was pale and sometimes contorted; this could make reference to the 1973 horror movie The Exorcist.
 * The title card has nothing to do with the episode, because it shows a funeral for Princess Bubblegum, with the characters looking into an open grave, despite the fact that PB does not die.
 * A stack of pancakes makes a cameo when the Candy People are worrying the 2nd time if PB will survive.
 * The strange thing about this episode is that Lady Rainicorn wasn't seen in it, even though Lady is PB's Loyal pet.