The Bad Luck Diamond

Nobita, who was casually walking, steps on a can, which hits and aggravates a dog, who attacks him, soon followed by Gian's savage assault. Just when he thought his calamity was over and returns home, Tamako trips and spills a batch of thumb tacks, one of them stabbing him in the feet, causing him to scream in anguish. Doraemon later finds a depressed Nobita sitting in his room after having shopped Dorayakis, and they discuss on his perils.

Unable to enlighten Nobita, Doraemon reveals a purple diamond. He demonstrates its effect by rubbing it on himself first, giving it to Nobita before attacking himself with a hammer twice. Instead of Doraemon being bruised by the impact force, Nobita was struck and yells in pain. Sheathing his hammer, Doraemon explains its capabilities in particular - any calamity suffered by the user who rubbed on themselves will be passed onto the current holder. He apologizes for hitting Nobita, who plans to fully eliminate his own misfortunes. Doraemon is unwilling and recoils in terror, prompting them to seek out for another host. As they depart, Tamako chastises Nobita for lethargy, and he briefly threatens her with the diamond before walking off, leaving her confused.

As they search for someone in particular to scapegoat, Doraemon advises him to simply leave the diamond on the ground for an unlucky individual to find, though Nobita proposes staying, curious on where will it end up. They hide behind a vending machine and observe, lamenting that none were retrieving it. However, when they hear Shizuka intent on grabbing it, they scramble to stop her. While Doraemon successfully steals it back, Nobita trips on a rock, harming Doraemon instead, and he throws the diamond on the ground after a brief rant. Inquired by Shizuka, Nobita claims he is oblivious to its owner and should be left alone.

Suneo ends up passing by. Not missing a single opportunity, he claims ownership of the diamond, and they allow him to walk away with it. Ironically, the duo are not confronted by further incidents - Senior citizens are removing cans from the road for safety precautions, and the dog agitated earlier on did not attack when encountering them, being tied to a leash by its owner. Nobita comments and bewails on the situation, desiring to confront yet another disaster. They quickly notice Gian angrily walking to them and he decides to provoke the already furious menace, who takes the insult and proceeds to batter him. Suneo interrupts, declaring his guilt and returns the diamond, causing Nobita to panic. He dodges a punch and dashes off while criticizing Suneo's untimely conscience. Before Gian can reach him, Nobita is saved by Doraemon with a Take-copter, and Gian angrily swears revenge.

Cruising through the sky, both were dismayed by the diamond's purpose never manifesting. Nobita decides to dispose of it, only for Doraemon to ingest the diamond when it is thrown upward, and he coughs. They descend on a playground, and just as Doraemon recognizes the grave scenario, Nobita was struck by a stray football, which then punches Doraemon's face. Attempting to return it, he falls over, and Doraemon is struck on the chin. He angrily berates Nobita for potentially having to bear with the latter's tragedies for eternity. Nobita responds with Doraemon's previous consolation, much to the latter's chagrin.

Having to walk home, Doraemon is forced to simply direct Nobita on every move, such as he wouldn't suffer. He rebukes Nobita's denial with the pattern of suffering they have both observed while pumping out warnings, until Nobita almost falls into a sewer, prompting them to instead take an aerial route again. Doraemon continues his angry remarks until a model aircraft rams Nobita's head from behind, which forces Doraemon to scream and eject the diamond. Repulsed by the experience, Doraemon lands and throws the diamond away.

Returning home, Nobita still wonders the current host of the diamond. Doraemon is also unaware, and assures Nobita that he will be free from all terrors befalling him. Overcome bu guilt, Nobita no longer wishes for someone innocent to suffer, and Doraemon is eager to help in recovering the dangerous object.

Despite embarking on an extensive search, Nobita and Doraemon were unable to locate the diamond. As he tries to warn a man who possibly has it with calamities, Nobita's accusation unintentionally enrages him, whose wrathful outburst knocks him to the ground. In spite of this, Nobita was unharmed by the impact, and he concludes with Doraemon that someone already has it. Doraemon quickly formulates a plan of bashing Nobita repeatedly with the hammer - whoever that's under its mighty pummels will be the culprit. Initially their attempts were futile, and Nobita demands more powerful strikes. He soon steps into an exposed ditch, and as Doraemon pulls him out, he finds himself insulated from it also.

Gian, who was the unfortunate and confused victim of the diamond, angrily rants on the mysterious incidents surmounting him. As he stumbles upon the duo, he punches Nobita with all his rage, only to be hit in the face, and he desperately screams, implying his possession of the diamond to them. Out of retribution, the duo agree to leave Gian with it for a little while longer. When Gian tries to strike Nobita yet again, he is brutally mauled. As he lays wailing in confusion, Doraemon and Nobita turn to each other smiling, as the episode ends.