In New Orleans, Superman and J’onn are battling two teenage villains, Tommy and Tuppence Terror, the Terror Twins. They knock them back into a warehouse out of sight of the public and the teens are surprised to come face-to-face with Superboy, disguised as Tommy. Red Tornado and Aqualad subdue them and Miss Martian takes on Tuppence’s form. When Tommy wonders what is going on, Batman tells the villains that their lookalikes are under arrest.
Superboy and Miss Martian are taken to Belle Reve Prison, along with Icicle Jr. and Mr. Freeze. Miss Martian remembers how Batman explains that the four ice villains that they apprehended several months ago have all arranged to be sent to Belle Reve, designed to hold super-powered villains. Batman figures that they’re up to something and sends Superboy and Miss Martian in undercover. They can’t warn anyone on staff about the charade since they don’t know who else may be compromised.
On the way in, Icicle Jr. flirts briefly with Miss Martian until a guard knocks him back. Once inside, Warden Amanda Waller addresses the newcomers and explains that they were control collars that can negate their specific powers and inflict pain and unconsciousness for disciplinary purposes. She introduces them to Hugo Strange, the prison psychiatrist, and warns the prisoners that Belle Reve is escape proof.
As they are taken to their cells, Miss Martian telepathically tells Superboy that her collar isn’t designed for her telepathic abilities. Icicle Jr. and Superboy are taken into the men’s wing and given a cell together, while Miss Martian is placed in the women’s wing with Killer Frost. They are all taken to the exercise facility and the villain explains that he knows all about the place because his father, Icicle Sr., runs the place. Icicle Sr. is with Captain Cold and Mr. Freeze as well as several super-strong villains: Brick, Blockbuster, and Mammoth.
The Riddler is attempting to impress Icicle Sr. without success and they send him away. Icicle Jr. goes over but Professor Ojo attacks him. Superboy defends his new friend and Brick prepares to fight. The guards watch and let the fight continue, while Professor Ojo recognizes Superboy from their previous fight. Miss Martian telepathically alters his memories to protect her teammate, while Icicle Sr. ends the fight, saying that Superboy has guts unlike his own son. He calls over Icicle Jr. with the other ice villains and says that they have what they need to break everyone out of the prison.
Later, new prison coveralls are delivered and Icicle Jr. tells Superboy to be sure and put them on. Miss Martian updates Aqualad but says that they have to let the prison break go through until they can figure how out it will be done and stop them. Hugo Strange then calls in Superboy and Miss Martian for some psychoanalysis. Miss Martian directs the conversation toward Superboy’s father-figure issues with Superman. When Superboy snaps at her, Hugo Strange says that they’ve had a major breakthrough.
Icicle Sr. goes to the laundry room where some new parts have been delivered and are kept in storage. The prisoners then watch the news and make sure that all of the League members are distracted elsewhere. Superboy asks Icicle Jr. why he doesn’t sit with his father, and the teen villain says that he’s not interested in getting his father’s approval. Icicle Jr. then asks Superboy for a shot at his “sister.” Mr. Freeze picks a fight with Icicle Sr. and the guards quickly subdue him and take him to Waller.
As they’re taken back to their cells, Icicle Sr. tells his son that they can’t reach Killer Frost. Superboy jumps in and says that he secretly has a telepathic link with his “sister. Icicle Sr. tells him to tell the women that the break is going down.
Mr. Freeze is brought to Waller and freezes his guard. She activates the collar but he breaks it and Waller orders a lockdown. All of the doors close and the guards go on alert, while Mr. Freeze easily subdues Waller and shuts down the collars. Once they’re free, the prisoners quickly take down the guards. Meanwhile, Killer Frost prepares to kill one of the guards and Miss Martian telekinetically stops her. When the villainess strikes against her, Superboy loses contact with his teammate.
Once Waller, Hugo Strange, and the guards are locked up in a cell, Icicle Sr. and the other ice villains focus their powers on the doors so that the super-strong villains can slowly break through the brittle metal. Superboy is unable to establish contact with Miss Martian, and lies and tells Icicle Sr. that everything is fine in the women’s wing. Icicle Sr. then sends them to the wall adjoining the women’s wing so they can break through while Killer Frost and her super-strong women do the same from the other side. As Superman pounds through the wall, he vows to Miss Martian that he’ll rescue her.
Brick boasts to Waller that despite the lowered temperatures due to the ice villains, the new prison uniforms have microtech thermal units that keep them warm. When he threatens to kill Waller, Hugo Strange intervenes and suggests that they keep her as a hostage, and Brick agrees.
Superboy comes up with a new plan and tells Icicle Jr. that the collars on the women prisoners have been activated, and suggests that they go to Waller’s office and reactivate them. Professor Ojo and two other villains, Hook and Abra, try to stop them and Superboy attacks them. Ojo remembers who Superboy is, but Superboy knocks him out and goes inside. After a minute he emerges and tells Icicle Jr. that everything is under control.
The collars activate and the male prisoners collapse. Icicle Sr., who removed his, realizes that they’ve been stopped. He goes to confront Waller and demands an explanation, but Hugo Strange intervenes and knocks him down. Mr. Freeze prepares to kill him.
Mr. Freeze takes Mammoth and Blockbuster to confront Superboy, having discovered that he went to the warden’s office and reactivated the collars. He attacks Icicle Jr. while Superboy takes on the two super-strong villains, and Superboy tells his all that Mr. Freeze is making a power grab. The two teens switch opponents and defeat them, and Superboy breaks through the wall. Killer Frost is waiting for him and reveals that she froze Miss Martian solid. He defeats her and goes to Miss Martian, telepathically calling for her to stay with him. Miss Martian, raised in a Martian environment with a lower temperature, is able to resist the cold and telekinetically breaks free. Superboy kisses her and she reverts to her normal form, and Icicle Jr. realizes that he’s in big trouble.
Later, Hugo Strange is reassigned as warden and Waller is out. He calls Icicle Sr. to his new office and the villain says that their plan worked. Despite the fact they were beat, they met their main objectives and the Light will be pleased.