Prue flips through the Book of Shadows by the light of a single lamp. A noise startles her and she turns and gestures, to discover that she has flung Phoebe into an old bed. Prue admits to being somewhat jumpy; she's found out that a group called the Triad are the ones that have been sending all the demons and warlocks against them. Phoebe notices it's a little bit cold in the manor; Prue forgot to pay the gas bill. Piper has been away in "the Heavens" with Leo for a month, and Phoebe wonders if she'll ever come back; they have not heard anything from her or Leo. Darryl calls about a murder suspect, Emilio Smith, whom he's tracking. Darryl is following Emilio through a rave. Emilio carves an inverted triangle, or rune, into his victims' foreheads. Prue opens the Book to the page on the Guardians, which use that same sign and offer protection to murderers who steal souls for them. Prue tries to warn Darryl off, but he pursues anyway.
Darryl emerges into a back alley and looks for Emilio, but Emilio clobbers him. Emilio is about to carve the rune into Darryl's forehead when a young woman spots him, panics and runs. He kills her and carves the rune into her forehead, and his Guardian absorbs her soul through a similar rune on his forehead.
Prue and Phoebe find the girl too late, but not too late for Darryl. Prue flings Emilio back and his Guardian appears. Remembering that Guardians can be killed like vampires, Prue flings an iron bar at him. However, it passes right through him. Phoebe suggests throwing it at the rune in his forehead. Prue flings another iron bar at the rune; this time it's a direct hit.
The police arrive and a paramedic examines Darryl. The paramedic congratulates the sisters on fighting off the attacker, but they are not able to say exactly how they did it. Darryl suggests concocting a story or else Emilio walks, and they'd best concoct it fast, because the assistant district attorney handling the case is coming. The ADA identifies himself as Cole Turner and asks the sisters if they saw anything; Phoebe, smitten, says she did.
At the arrangement, Cole is fairly certain the judge will keep Emilio in jail, even though the weapon has vanished. The arraignment begins with Judge William Hamilton presiding. Cole stands by the police report and the eyewitness testimony. The public defender, Alan Sloan, pounds on the absence of the alleged murder weapon. Cole does his best, presenting evidence that would normally be enough to keep a murder suspect in jail. However, the judge drops the charges.
The next day, Phoebe is visibly frustrated that Emilio walked. However, Prue fears they could not have done any more than they did without exposing themselves as witches. Phoebe seems taken with Cole. Leo and Piper orb in arguing; Piper wants to be together, no matter what "they" think, but Leo has cold feet. Piper freezes Leo and heads for P3, she unfreezes him as she leaves. Phoebe starts to scold Leo, but Prue calms her down and asks Leo to ask "them" about the Guardians. Phoebe wants to follow Piper to P3 and talk to her about leaving for so long, but just as she's about to head out, Prue telekinetically closes the door. Phoebe states that they had a deal that Prue wouldn't use her active power on her until she has an active power to use back. Prue thinks that since she's the cooler head, she should be the one to talk to Piper.
Piper finds the food and drinks nearly gone and the books all messed up. She had thought she was gone for a day, but was in fact gone for a month; apparently time moves slower "Up There." Prue asks Piper about "The Heavens" and she reports mostly good and peaceful feelings, until "they" told Leo and Piper to stop seeing each other, or else "they'll" revoke Leo's assignment as their Whitelighter. Prue thinks Leo will fight tooth and nail to stay with Piper, but Piper is not so sure.
Phoebe is on campus and Cole taps her shoulder. She turns and high-kicks, but Cole catches her leg. After complimenting her, he notes that the judge is called "Free Willy" for his high release rate, and asks for her help in building a better case. Phoebe has a premonition from Cole's business card of Emilio carving the rune into Cole's forehead. She goes to P3 to warn Prue and Piper. Piper is still in the dark about everything, and Prue has to keep Phoebe from biting her head off. Prue and Phoebe head out after Emilio.
Emilio enters Judge Hamilton's office and asks for a new Guardian. Hamilton conjures an athame and sends Emilio after Cole.
At the precinct, Cole asks Darryl if he knows anything, but Darryl has already told everything he knows. Both are frustrated that Emilio walked. Cole notices that Darryl called the manor late yesterday morning. Darryl explains that since the sisters own P3, he thought they might be interested in checking out the rave. Just as Cole is about to leave, Phoebe calls on his cell phone; she and Prue are headed for the precinct. Phoebe tries to warn Cole, but the signal mysteriously goes south.
Emilio finds Cole in the police parking garage and clobbers him from behind. He raises the athame as Prue and Phoebe squeal in. Phoebe tries to high-kick Emilio, but instead levitates six feet in the air, much to her and Prue's surprise. Prue flings Emilio into a car as Phoebe falls back down. Prue launches the athame into the Guardian's rune, vanquishing him.
Leo practices a marriage proposal before a bathroom mirror and Piper overhears. Piper walks in and asks about the Guardians, but Leo forgot. Leo wants to go downstairs, but Piper insists on talking right there. Much to Piper's surprise, Leo drops to one knee and asks Piper to marry him. Piper runs downstairs. Leo thinks that a marriage would be a holy union that even "they" could not break apart. However, they'll have to elope to keep "them" from finding out. Piper does not like the idea of an elopement, and will not marry Leo under these conditions. Prue and Phoebe come back in. Leo admits he hasn't gotten any word about the Guardians, and orbs out to check with "them."
Darryl has interrogated Emilio in vain. Cole walks in and tells Emilio that he knows someone is protecting him, but probably won't be able to for much longer. Cole knows that someone sent Emilio after him, and wants Emilio to tell that someone that Cole will personally bring him down. Emilio scoffs at him, and Cole lunges at him; Darryl has to separate them.
Prue and Phoebe find Piper alone in her room. Piper tells them that Leo proposed to her, but isn't sure if it'll work. Phoebe thinks it will, since their love is so strong. Leo orbs in and tells the sisters what "they" told him about the Guardians. "They" think Hamilton's courtroom is enveloped in a demonic conspiracy; apparently an upper-level demon is assigning Guardians to the criminals Hamilton is setting free. Prue initially suspected Sloan is the demon, but doesn't think he's in a position to set criminals free. Phoebe thinks that Hamilton himself might be the demon, given his high release rate.
The sisters and Leo go to court; Emilio is due to be arraigned in night court. Prue and Phoebe think that Piper can smoke out the demon by freezing only the innocents in the room. In court, Cole asks for a word with the sisters, but Hamilton turns him down. Piper tries to freeze only the innocents but it doesn't work.
At Prue's insistence, Piper freezes the courtroom again and as expected, the judge and Emilio don't freeze--but neither do the PD or the bailiffs. Hamilton spots the sisters and orders them killed. The sisters run and hide. Hamilton reveals his demon form.
The sisters hide in the jury room. Emilio and the courtroom personnel try to break in, but can't get through. Hamilton, back in his human form, throws fireballs at the door, to no avail. Prue blows the door open, sending everyone flying about.
Alan pulls a gun on Prue, but Prue flings him into the jury box. Phoebe engages the female bailiff. Emilio goes in on Piper and grabs the athame, but Piper blocks it with one of the bailiffs' batons.
Prue kicks down one of the bailiffs. Hamilton throws a fireball at Prue, but Prue deflects it into the bench. Phoebe gains some control of her levitation while the scuffle continues. Hamilton throws another fireball at Prue, but Prue deflects it away. Several Guardians rise out of Emilio and the courtroom personnel and follow Hamilton into his chambers.
Cole suddenly starts moving; he only pretended to freeze. This is the first sign he's no mere DA. He shimmers into the judge's chambers and gestures, sending Hamilton up in flames. He shimmers out and the sisters find the judge already in flames. They come out and Phoebe knocks Cole out. Cole comes to, and Phoebe tells him that everyone in the room tried to help Emilio escape, but Darryl saved the day.
The Barenaked Ladies play P3. Piper meets Leo and says she thought she might have died in that courtroom. She agrees to marry Leo.