Michael recieves medical attention. Charles Westmoreland helps uncover the real secrets of Scylla. Lincoln and Sucre do everything in their power to retrieve Scylla before it's gone forever.

Gretchen and Self wind up with Scylla (and a buyer). Michael battles with the Company for Scylla. Mahone asks some familiar faces for help. T-Bag continues to hold a couple of innocents hostage.

The General works to regain Scylla. T-Bag gets a new partner. Michael and Lincoln have an important meeting.

Sara takes a hostage in a bid to secure Scylla. Michael and Lincoln finally meet the General while one of their members switches allegiance.

Michael risks his life by breaking into the Company headquarters along with the others. Gretchen tries to get the last card with a meeting with the general. Trishanne's days may be numbered.

Sara is left with no choice but to take Michael to the hospital as his condtion rapidly worsens. Sucre and Lincoln are faced with unknown territory as they are left in charge of the operation. Agent Self makes a surprising ally.

Michael, Lincoln, Sucre and Bellick tunnel into the Company's headquarters. Gretchen meets with Pad Man. Michael's condition continues to deteriorate. The police question T-Bag regarding Andy's disappearance. Wyatt propositions Sara while Mahone awaits his shot at his son's killer.

Lincoln works to retrieve the final card, which is being held by the General. Michael and Self are forced to work with Gretchen. Meanwhile, Roland continues to be berated for losing the transcribing device in Las Vegas.

Lincoln, Sara, Sucre and Roland travel to Las Vegas in order to retrieve the next card. Gretchen recruits T-Bag. Wyatt tracks down Self.

The entire operation may be in jeopardy when Mahone gets into trouble with the law. Gretchen's sister receives a surprise visitor. The Company may be onto Self. T-Bag continues to raise suspicions at Gate.