Daddy's boys. Perry's ex-con son and Mr. Gadget's cop son bring their own brands of evildoing to Metropolis.
Perry's son, Jerry, gets out of prison for good behaviour and Perry tries to rebuild their relationship. He showers his father with surprisingly expensive gifts. It is later revealed that Jerry has a case with red Kryptonite in his possession which is making Superman unable to control his powers while he pulls off successful robberies.
The effects become worse making him unable to do certain things such as warming up a mug of coffee when he starts melting the entire mug and causing a typhoon when he sneezes.
Superman, not knowing what is going on, tries to find it out with Dr. Klein's help while he stays away from Lois and everyone as much as he can so he will not hurt them.
Meanwhile, the insane Mr. Gadget and his policeman son Carter find out about the Kryptonite and hire Jerry to use it against Superman so they will be able to hold the city for ransom in exchange for one billion dollars or else they will destroy the city with a sonic device.
Jerry at first refuses but after his father is threatened to be killed, he has no choice.
Superman decides to stop Mr. Gadget, but the Mayor is still convinced that Superman's powers still may go out of control so she sends a policeman with a gun loaded with green Kryptonite bullets to attack if necessary.
The Man of Steel finds the sonic device, but as he is about to destroy it, Jerry is using the Kryptonite again.
Perry sees what his son is doing and convinces him to stop. Jerry then tells him who is behind all this. Superman successfully destroys the device and Metropolis is safe.
Angry at Jerry's betrayal, Carter then tries to shoot Perry, but Superman wraps him up from hand to foot. The policeman thinking Superman is out of control shoots him, but luckily the bullet only grazes him.
Mr. Gadget tries to escape, but Superman chases and captures him. Mr. Gadget and his son are imprisoned and the police then arrest Jerry for his involvement and the robberies. Jerry apologises and hugs his father promising that he really will change his ways when he gets out of prison.
Superman has his powers under control again because the green Kryptonite substance counteracted the red substance.