At the prison, Michael's going over the escape plan with Juan. But a couple of guards come to take them out of their cells, which Michael takes as a sign that "Cruz's party is about to get started." Sure enough, the guards lead Michael and Juan to Cruz's cell block, where the security cameras are all torn out and Cruz is waiting in a tiny, screened-over courtyard with some goons armed with pipes. They start by beating down the guards, and while the rest of the prisoners on the other side of the glass -- and indeed, throughout the prison -- start getting wound up and the guards start to respond, Cruz starts in on some big talk about what he's going to do to Michael and Juan. So Michael starts some beating of his own. He handles the goons while Juan handles Cruz, if by "handles" you means "gets curbstomped by." By the time Michael is free to come to Juan's rescue, Juan's leg is broken and the riot is starting in earnest. Michael insists on dragging Juan toward the infirmary, but Juan says they'll never make it with his injury. Michael insists that someone's going to have to leave by the route they planned; it'll just have to be Cruz.
He gets on the phone to Sam and Jesse, who are getting checked in at the gate in their borrowed guard uniforms. You know, in the middle of a prison riot. Michael hides Juan in one of those giant wheeled laundry bins that come in so handy in prison breaks (they really need to start making those out of clear plastic) while telling Sam the new plan.
Sam calls Hill to have him get word to Cruz that Michael and Juan are hiding in the infirmary. Where Michael has just entered, and has gotten to work MacGyvering a little welcoming party for Cruz involving oxygen, ether and rubbing alcohol. Cruz and his guys are quick to arrive, and Michael uses a dental butane torch to light the alcohol he poured on the floor, which leads to the oxygen tank he just tossed in their direction. The place gets blown to shit, of course, but as always the explosion is just large enough to only knock out the bad guys without killing anyone. Sam and Jesse arrive a few seconds later, and Jesse takes in the devastation and dryly says, "Yep, this looks about right." Sam can't resist quipping, "I guess Cruz finally got a taste of his own medicine," but he at least feels bad about it. They load the unconscious Cruz into the drug locker and haul him out while Michael dials Agent Harris. "You said to call if there was trouble?" And Michael is nothing if not obedient.