The episode opens with Phineas and Chris laying in bed waking up at 6am. Chris decides that since it's the last day of summer, they need to make an ultimate memory device. Around 9, work begins. They build 5-6 prototypes before being fully finished. The two activate the device to relive the pool party that was held when Chris arrived (and almost caused a series end in the pilot). Suddenly, an overheat causes the devices to almost blow, but instead, catch fire. Phineas frees himself but doesn't have enough time to save his brother. He is rushed to the hospital for urgent care. That night, Phineas develops a horrible nightmare about his brother being tortured to death. The next day, he and Candace are required to stay out of school until news about Chris comes in. Candace starts to ask Phineas deep personal questions. Just before a very painful one could be asked, Ferb (by all means) comes in as a foriegn transfer student to Danvillie Elemantary. While Candace and Linda are happy, Phineas still sits and thinks (almost putting himself in a coma) about the questions Candace asked. Thinking he should get out, Ferb treats Phineas to a cheeseburger to take his mind off things. Phineas runs into Isabella who is wondering where Chris has gone. Phineas asks not to talk about it. She insists he tell her. He sucks in his gut and says Chris is in the hospital from a deadly accident. She has a flashback about meeting Chris for the 1st time. At home, Linda talks to Phineas before he goes to bed about Chris, about why he is so worried. Phineas is so worried, he turns it into song form. Just before they can go to sleep, a phone call from the hospital comes in. They ask they come and bring friends. They gather into his room as they learn Chris is going to die within the hour. Phineas, desperate to hear his brother's voice, begs for him to awaken. He awakens, but is very weak. He goes around saying things about all the ones around him. He turns to Phineas thanking him for helping him out by being a brother and a friend. He says to remember him for his nickname "Prime". He then asks Ferb to watch out for him. By 9, his eyes flicker, blink, and fade. Christopher Flynn has died. While walking out of the hospital, Ferb comforts his brother as they walk out. He stands in front of his brother, holds his arms out high, and gives his brother a hug. Phineas, not wanting to leave his brother, runs back to his room and wraps his body in a brother hug crying his eyes out that he loved him and won't let him die. The doctor pauses in a moment of silence to let Phineas have a moment. Over the wails of his crying, the heart monitor, although slow, starts beeping. Chris slightly awakens. and puts his right hand over his brother's hand and, to Phineas' delight, is alive. Although to be 100% of his cure, he stays overnight and returns to his family the next day.
Doctor: I'm sorry son. He'll be dead within the hour.
Phineas (choking off words): Chris, don't die on me man. I can't lose another brother.
Chris: Don't grief. Soon...I shall be one with the brotherhood.
Chris: F..Fe...Fe. Ferb, it is to you my friend. I must pass brotherhood...as it was given to me.
Ferb: But Chris I...I'm just a visitor. I can't watch Phineas.
Chris: Nor could I. But one day. Someone will be born of our blood. And use my ability...to light your darkest hour. Brother...come closer.
Chris: Don't forget me. You made me a hero for this town. You made me a...friend. Remember me for my name?
Chris: No. The other one....Prime.
Doctor: Son. He's going soon. Better hurry.
Phineas (starting to cry): Please don't die. PLEASE!!!
Chris: Until another comes...goodbye...bro.
Phineas: No. He can't be gone. No, no. NO!!! Why? Why would he die on me?
Ferb: Come here. Come on. Give your old man a hug. I'm sorry Phineas but he's gone. Oh come now, don't cry. In my country, crying is for quitters.
Phineas: Do I look as though I care? My brother is dead. I'M ALONE!!!
Isabella: Oh come on. You've got us. We'll be there for you.
Ferb: Your gonna be okay.
Linda: Uh, Ferb. Not that it's trouble with your transfer parents but...could you stay here with Phineas until he feels okay?
Ferb: Of course.
Phineas: No. I won't leave him! Chris, I'm sorry I killed you! I blame myself. I love you brother, come back to me.
Doctor: Do you need a moment? (Phineas nods)
Chris: (slightly opens his eyes and places his hand on Phineas' back) You didn't think I'd leave did you?
Phineas: CHRIS! Your alive!!!
Linda: Oh, it's a miracle.
Ferb: I guess you won't be alone after all. Chris: Get me out of this bed, and let's go home.
Where Did I Go Wrong: Performed when Phineas was thinking Chris would die.
Phineas' Nightmare: Performed by Buford in Phineas' nightmare. Lyrics are similar to those of the Oogie Boogie song.
- This is the final episode of season 1 of Phineas and Chris.
- The song "Where Did I Go Wrong" is similar to "Where Did We Go Wrong" Performed in Phineas and Ferb's Christmas Vacation.