J-Cat is the 17th episode in the season. In this episode the convicts must find ways to cover up their plans from the guards.
After Dr. Sara Tancredi tells Warden Pope about the burnt fragment of a guard's uniform found in Michael's burn, Pope questions Michael about it. When he refuses to answer, Michael is sent to the Solitary Housing Unit (SHU), where Lincoln was also being held. Lincoln is worried about Michael's sanity while Michael has trouble remembering some parts of the prison schematics. While in solitary, Michael appears to have an emotional breakdown. He begins punching the wall repeatedly, fists bleeding, and repeating the words "I put my blood into this."
The PI works in the guard room are coming to an end by surprise. Being the only one who has access to the hole behind the toilet in his cell, Sucre is forced by the other escape team members to conceal the hole in the guard's break room. He asks T-Bag to get a pair of panties from a cross-dresser by offering a sexual favor. T-Bag is reluctant but he gets the panties.
Veronica and Nick use rope to lower LJ into the well where Quinn's body is to grab Quinn's cell phone. LJ sees Kellerman's name etched on the well wall and realizes what part Kellerman played, but doesn't say anything to Veronica or Nick. Later, they leave LJ in the apartment. LJ uses a quick computer research to find Kellerman's house. He breaks in while no one is home, but a neighbor woman sees the break in and calls the police. When Kellerman returns home, LJ pulls a gun on him. Kellerman is shot, but not seriously injured. The police arrive and LJ is arrested.
Meanwhile, Sucre manages to conceal the hole but is caught when making his way back to the cell. Bellick interrogates him and when Sucre denies an escape attempt, he demands a reason. After Bellick finds the cross-dresser's panties hidden around Sucre's ankle, Sucre says they were his girlfriend's and uses them as his excuse: "She wanted to let me know she's thinking of me." He is also thrown into solitary.
Lincoln tells a guard to check on Michael after he stops responding. The guard immediately calls for medical help as Michael is found catatonically staring at the wall with bloody fists. He is cleaned up by Sara and put into the psych ward. Michael then snaps out of his disturbed state, revealing it was all a ploy in order to talk to Haywire. Michael asks Haywire to remember the tattoo on his (Michael's) back because the map had been burned off. Haywire just replies by asking "Who are you?", revealing that he is apparently back on his medication.
- J-Cat is slang for a prisoner that needs mental health treatment. It is sometimes referred to as a "Cat-J."
- When the carpeters arrive, the company van says "Muensch's Carpets".
- This marks the fourth time that John Abruzzi doesn't appear in an episode.
- This marks the first appearance of Charles Patoshik since Cute Poison, a re-appearance of 13 episodes.
- Michael thinks in flashes about what he has all done in Fox River. Lincoln and Sucre ask for Michael, but he doesn't respond. Thus Lincoln screams for a guard.