After receiving his daily water ration, Michael tells McGrady, the young Panamanian inmate, that he's looking for James Whistler. It turns out that everyone is looking for Whistler, who killed the the mayor of Panama City's son. Michael and McGrady's conversation comes to an end when a scuffle breaks out at the front of the water line. The fight knocks the water drum to the ground, emptying the contents. Lechero promises the thirsty inmates there will be more water.
Michael questions Bellick about the note he slipped into his pocket. Bellick says the note came from Whistler, who is hiding in the sewer system beneath Sona. Michael locates Whistler in a ghastly tunnel, holed-up behind a wall. Whistler tells Michael that if he leaves his sanctuary and goes above ground, the other inmates will kill him.
At a restaurant in Panama City, Lincoln meets with Susan B., who demands a daily progress report on his efforts to locate Whistler. Sara and LJ will be released once Whistler is safe.
Back at Sona, McGrady tells Mahone that, according to Lechero, whoever finds and kills Whistler will end up a free man. It doesn't take Mahone long to find Whistler's hiding place. Using a pipe, Mahone pries loose chunks of wall, digging a panicked Whistler out of his sanctuary.
During visitation, Michael passes Whistler's note to Lincoln. Michael still doesn't know what the note means, but feels it might buy them some leverage. After leaving the penitentiary, Lincoln spots Sucre at a bus stop. Lincoln asks Sucre for his help in freeing Michael, but Sucre is heading to Chicago to see Maricruz. Lincoln tells Sucre that if he changes his mind, he's staying at the Plaza del Sol hotel. As Sucre's bus pulls away, Lincoln notices an advertisement on the back of the bus for Banco de Versailles. Lincoln opens the note Michael gave him. It reads:
Meanwhile, Sofia studies the same text, written on a different piece of paper. She heads for the bank.
At Sona, Bellick informs Lechero and his men that Whistler is hiding in the sewers. Michael notices Bellick leaving Lechero's room-and realizes he's got a big problem on his hands. Michael races back to the sewer, where he encounters three of Lechero's men. It turns out that their attempt to capture Whistler was stopped by Mahone, who has one hand around Whistler's throat and is brandishing a pipe in the other. Whistler breaks free of Mahone's grip and runs off. He's pursued by Mahone and Lechero's men.
With time running out, Michael makes his way to Lechero's room, where he tries to broker a deal. Lechero isn't interested. Michael then approaches McGrady in the yard and pays him to bring a gallon of moonshine to his cell.
Sofia arrives at Banco de Versailles, where she hands the note to a bank employee. The employee tells Sofia she's a signatory on Whistler's account. Unbeknownst to Sofia, Lincoln is observing nearby.
Back in the sewer system, Lechero's men advance on the outnumbered Mahone. But Mahone fends them off with the pipe and forces Whistler toward the exit.
At a bus stop in Panama, Sucre encounters a young mother and her baby. Some policemen happen by, prompting Sucre to have second thoughts about continuing his journey to Chicago (as his presence could put Maricruz in jeopardy).
The bank employee brings Sofia a safety deposit box. Sofia reaches inside and removes the contents. When Sofia exits the bank, Lincoln confronts her. He reaches his hand into her purse and removes what she took from the safety deposit box: a pocket-size book on birds. In the distance, Agent Pike witnesses the exchange.
Meanwhile, an angry mob of protestors gathers near Lechero's room. They demand more water. Lechero phones his supplier, Colonel Escamilla, but is unable to convince him to bring more water to the prison.
Mahone forces Whistler into the yard, where they're swarmed by inmates. Lechero attempts to take control, but Wyatt tells him that, because of the lack of water, he's now powerless. At that moment, Michael detonates bags of moonshine he's stuffed into a sewer pipe. The explosion causes water to gush from a pipe in the yard. Inmates rush toward the gurgling liquid-and Lechero realizes Michael is responsible for the turnaround. Lechero informs Mahone he's been outbid and, in a sign of gratitude, tells Michael that Whistler is now in the clear and won't be killed.
Susan B. confronts Lincoln and demands what he took from Sofia. Lincoln gives her a small book, but it turns out he has the real book (the one Sofia gave him) hidden away.
At the prison, Lechero has his men drown Wyatt in a bucket of water. Meanwhile, Michael tells Whistler he has no idea how they're going to escape.