With Abruzzi becoming more desperate to regain authority within the prison, it seems that Fibonacci's number is up.

Michael gets a visit from his wife, while Veronica and Nick get a visit from Quinn.

C-Note overhears Michael and Lincoln discussing that there are too many fugitives for available time and they share the information with the group telling that one shall be left behind. T-Bag feels threatened and calls his cousin James Bagwell, disclosing the escape plan and asking James to call the Warden Pope in case T-Bag does not contact him later. Abruzzi asks his outside man to kidnap James, but things go wrong and the mobster kills James and his five year old son Jimmy. Abruzzi feels guilty for the death of the child and feels the need of God's forgiveness, but T-Bag betrays Abruzzi like Judas. Meanwhile Veronica and LJ bring Nick to the hospital and while in surgery, LJ escapes to see the funeral of his mother. Daniel Hale sees the teenager in the cemetery but he does not arrest him; later he tells his wife that they should move West and makes an anonymous call to Veronica scheduling a meeting in the Highland Cafe. Maricruz tells Sucre that she is pregnant but she will marry Hector. Captain Bellick presses David to rat Michael, reporting everything he says. Michael tests the escape plan and informs the group that they are ready to go that night, but Lincoln was sent to solitary confinement protecting his brother.

With the pipe to the infirmary replaced and Lincoln's life hanging in the balance, Michael must rethink his plan to escape and save his brother's life. A fellow inmate may hold the key to preventing Lincoln's execution.

Having burned his shoulder, Michael's tattoo that showed the path through psych ward is now incomplete. With another inmate intimidated into snitching about the escape plans, Michael Scofield must use his wits to find a new way out of Fox River.

After the crash Kellerman tries to suffocate Lincoln, but he is saved in the last moment by a stranger. Sucre leaves solitary confinement and Michael tells to his partners that he has completed the map, but he needs the key to the infirmary. Abruzzi is back to Fox River, apparently converted into a religious man. Warden Pope sends Captain Bellick to find Lincoln before notifying the authorities. Nick tries to convince Veronica that they are losing time checking the calls of Quinn's cell phone. Michael kisses Sara and asks her to wait for him. Tweener is in trouble with Avocado and he castrates the abuser. Lincoln sees that the stranger is actually his father, and he explains that he worked for the powerful Company and Lincoln is a victim of a big plot against him. He had leaked information of EcoField and they used Lincoln to force him to show up. Michaels asks for help from Nika. Veronica finds many calls from Montana on Quinn's phone. The Vice-President tells her brother that he is alive just because of her, and he replies that he does not understand how they have not killed her yet. Abruzzi meets T-Bag and asks him to forget everything, and they make a truce. Nika seeks out Sara and tells her about her life and how Michael helped her, but she actually steals Sara's key. A guy sees the Mustang in a junkyard where Aldo and Lincoln are hidden, but Kellerman bugs the conversation and goes to the spot. However, the police arrive and Captain Bellick arrests Lincoln, saving him from Kellerman. Sara seeks her key and recalls her meeting with Nika Volek; she calls maintenance service to replace the lock. Nick works for Abruzzi. Michael invites David and he betrays the plan to Captain Bellick. Lincoln is back to Fox River under 24 hours surveillance.

Westmoreland uses Bellick to plug a hole in the escape plan, which forces Michael to move up the breakout timetable. A fearful Tweener pledges his loyalty to Michael and in return may get out of jail for free; Michael feels that he has no choice but to involve Sara in the plan and must betray his father figure; and Veronica finds her life in jeopardy from her closest ally, who has a surprising connection to a Fox River inmate.

The team start the escape from the hole in Scofield's cell.

As the escape continues, lives are lost and Pope and Bellick do everything in their power to capture the convicts.

The F.B.I agent Mahone decides to use L.J to get to Michael and Lincoln by cutting a deal with him and making him trick the two fugitives into revealing their location. Michael and Lincoln decide there's only one thing they can do, rescue L.J in a daring raid at the county jail. Only one problem though, Mahone is personally guarding L.J and won't let him out of his sight.

With hospitals and clinics under surveillance, Michael brings Lincoln to Nika's home to heal his wounded leg. Then he returns to the place where he parked his Accord and finds that the car has been towed. Meanwhile agent Mahone retrieves Michael's backpack with his passport from a vagrant that broke the rear window of Michael's car to steal the backpack. Michael goes to Brewster Towing yard to recover his car. Meanwhile Sucre finds that Maricruz will marry Hector in a couple of days and he heads to New York in a stolen car. Sara is arrested and her father visits her, pays her bail and orders her to tell a fake version about the incident in Fox River since he will be the next Vice-President of United States. Later she goes to rehabilitation where Kellerman is pretending to be an addicted patient. C-Note schedules a meeting with his wife, but his conversation is bugged by agent Mahone. Bellick and Geary meet each other by chance and later they team-up to get the $400,000 reward for capturing Michael and Lincoln. They go to Fox River and Bellick interrogates Manche Sanchez, who discloses the plan of the fugitives. Michael and Lincoln forge a car accident to escape from Mahone, but they do not see that Bellick and Geary are in their tail.

Michael, Linc, and Nika are captured by Bellick and Geary, who intend to retrieve Westmoreland's money in Utah. Tweener continues his drive with Debra Jean. Abruzzi is reunited with his wife and children and is set to flee the country with them, but decides to take care of Fibonacci first. T-Bag has a close call with the police at a Nebraska gas station, and then poses as a Marine who lost his hand in Iraq. Mahone waits for confirmation of the deaths of Michael and Linc in the car explosion, and meanwhile gets a lead on one of the other fugitives. Kellerman (posing as a recovering addict named Lance) befriends Sara.

Michael and Linc arrive in Tooele, but the map they need to locate the double-K ranch is missing. They run into T-Bag and Tweener, who have also come to Tooele for Westmoreland's money. Meanwhile, C-Note makes his way by train toward Tooele. Sucre reaches Las Vegas and attempts to halt the wedding of Maricruz and Hector. Sara invites Kellerman to her apartment, believing he is harmless. At the FBI office in Chicago, Mahone reviews files recovered from Michael's hard drive, and begins to piece things together.

Mahone arrives in Salt Lake City, trying to locate exactly where in Utah the escapees are. Michael and Linc hatch a plan with T-Bag and Tweener that will enable them to dig in the right place. C-Note and Sucre meet on the highway and head toward Tooele. Kellerman, in Washington, D.C., briefs Kim. Governor Tancredi phones Sara with a warning.

Michael's plan has hit a snag when the home owner's daughter, a cop, arrives. Mahone argues with Lyle Sands about how to proceed, but ultimately hopes that Tweener, in FBI custody, will reveal the location of the other escapees. Sara is now suspicious of Kellerman, so he tries something different to find Lincoln Burrows. In an Arizona detention facility, L.J. finds out he's to be released the next day; Linc drives to get him. Haywire, in Wisconsin, steals supplies from a camping shop.

In Cutback, Montana, Kellerman lures the police and Michael and Lincoln abduct the cameraman Greg of Fox News and succeed in escaping from the siege. Michael and Lincoln decide to tape a message to be released in the Breaking News. Mahone is back in Chicago and analyzing the message; he interrogates Greg and he tells that he had overheard Michael tell that they should cover 460 miles in six hours. Mahone deduces that they intend to meet President Caroline in Denver. Wheeler discusses with Mahone and yells that the Internal Affairs department asked him to follow all moves of Mahone. Bellick is badly wounded in the infirmary of Fox River. Sucre befriends an old passenger in a bus to Ixtapa; however the driver asks him to leave the bus in a small town and Sucre robs the Volkswagen of the old man. In Algoma, Winsconsin, Haywire befriends a young couple and the girl has bruises on her arm; she tells that her abusive drunken father beat her.

Michael is once again imprisoned, but now in SONA (Panama), together with T-Bag, Mahone and Bellick. The prison is solely ruled by inmates, whose local prison-lord Lechero feels threatened by Scofield's 'fame'. Lincoln tries legal means to get Michael transferred, and gets a call from a relative. Both receive the same message, through different channels, from The Company.