Ronon and Teyla are on a mission and talking about her new child, and the fact that Kanaan is getting reaccustomed to living back on Atlantis. They notice a cloaked figure and got to investigate, but the figure knocks out Ronon. He gets up and pulls off his hood, and Teyla recognizes him as Tyre, Ronon's former Satedan comrade. Tyre stuns her as well and leaves with Ronon.
Teyla recovers and goes back to Atlantis to update the team. They meet with Woolsey and determine that they can't find a signal from Ronon's subcutaneous transponder. Teyla notes that although Tyre was unstable last time they met him, he spared her life rather than kill a witness. They decide to get another Satedan's help: Solen Sincha, who survived the Wraith attack on Belkan. They head out, then stop long enough to get Woolsey's authority. As they go, Woolsey notes that Teyla hasn't said she returned to active duty. She admits that she hasn't fully decided yet, but is going on this mission because of her familiarity with Solen.
Ronon wakes up tied to a chair. Tyre has taken him to a planet and has him hidden in an abandoned building. Tyre reassures Ronon that Teyla is fine and that they should be comrades, not enemies. Ronon notes that Tyre betrayed him the last time they met, and is a traitor to the memory of Sateda. Tyre says that Ronon has been blinded by his new allies but he'll help both of them. Tyre's hands shake and Ronon wonders what his problem is. Tyre says that they're on Sarif Sur where they almost died before during a mission. Ronon didn't abandon him then… and Tyre isn't going to abandon Ronon now.
Sheppard's team finds Solen in a bar and explains the situation. Solen isn't impressed and tells them that the Wraith have cut Tyre loose after he failed to bring in Ronon. Solen isn't happy with Tyre and plans to kill himself, but Sheppard convinces him to let them know when he finds Tyre so they can deal with the traitor.
Ronon offers to help Tyre, who reveals that he's suffering from withdrawal after being cut off from Wraith feeding. Tyre tells them that he already has help planned… and a Wraith commander arrives with his soldiers. The Ronon says it's been a long time since he's encountered Ronon… and then starts draining his life force.
Woolsey talks to Teyla, who apologizes about the fact she hasn't made a decision yet. She says that she's considering her priorities and what's most important. Woolsey sympathizes, saying that he had to reorder his priorities when he was assigned to duty in another galaxy. He notes that Kanaan will support her no matter what decision she makes.
The Wraith Commander drains Ronon and asks him how it feels. Ronon refuses to give in, and the Wraith begins draining him again.
McKay meets Sheppard for breakfast and admits that he has been up all night trying to come up with ideas. They try to figure out what they're overlooking when they receive word from Major Lorne that Solen has called to inform them that Tyre is on Sarif Sur.
During a break in feedings, Tyre warns Ronon that he should just give in. Ronon doesn't believe him, figuring Tyre's just trying to get back into the Wraith's good graces. The Wraith commander returns and say s they're going to take Ronon to his Hive facility. Tyre demands that the Wraith honor their agreement and take him back, but the Wraith casts him aside and leaves.
Sheppard and the others arrive at Sarif Sur and find Tyre. They take him back to Atlantis where Keller confirms that the Satedan is going through withdrawal. She warns that it may be days before Tyre has recovered enough to tell them anything. Teyla confronts Sheppard and wants to know why he didn't take her on the mission, and he tells her that Woolsey's pressuring him to find a team replacement and she needs to make a decision one way or another.
The Wraith commander takes Ronon to his facility and taunts Ronon. He points out that Ronon's friends died not because they were too honorable, but because they weren't strong enough to handle the brainwashing. The Wraith notes that Ronon is strong enough, and that's what will let the Wraith break him.
Keller is forced to put Tyre in isolation as he goes berserk. Sheppard refuses to allow him to receive sedatives so that he'll recover faster and tell them what they need to know.
Teyla is in her quarters with Torren when Kanaan arrives. She admits that she feels a responsibility to her new son, but Kanaan says that she also has a responsibility to the galaxy and making sure they all have a future. He tells her that she needs to follow her heart no matter what.
Tyre finally gets through his withdrawal and tells Sheppard that he knows where Ronon is. He insists on leading the team into the facility and promises not to betray them.
Ronon has given in: he recites a vow of loyalty to the Wraith, and his torturer gives him his sword and sends him out to fight their now-mutual enemy: Atlantis.
Woolsey is concerned about Tyre's involvement in the mission but Sheppard believes that Tyre is honestly trying to redeem himself. Teyla arrives, carrying Torren, and insists on going on the mission. She hands the baby off to Woolsey and leaves with Sheppard, and Woolsey hastily tries to find Kanaan.
Arriving on the planet, Tyre leads Sheppard's team through the Wraith facility, planting explosives. Sheppard shows him how the remote detonator works. They find Ronon but the Wraith commander is there with his men and takes them captive. When Sheppard considers fighting back, Tyre takes Teyla hostage and demands that the Wraith honor their agreement. The Wraith Commander agrees and Ronon and Tyre are reunited.
The team is separated and Sheppard's team is locked up separately from Lorne and his soldiers. McKay tries to come up with a plan and suggests that they try to get Ronon alone and hope that his recent brainwashing doesn't hold. Tyre arrives to take Sheppard to the Wraith commander, having convinced his leader that the team is more useful alive and brainwashed to loyalty.
Tyre takes Sheppard through the facility but takes a detour. A few minutes later, they arrive in the Wraith's quarters and the commander prepares to start draining Sheppard. As he reaches out… Tyre cuts off his hand, then fights Ronon. Sheppard has his gun and starts shooting the soldiers. Teyla and McKay escape from their cell, as Tyre went back and freed them. They get to Lorne's cell and free him and the others.
Ronon finally defeats Tyre but Teyla and the others arrive and stun him. Sheppard threatens the Wraith but it would prefer to die. However, Tyre threatens to activate the explosives and destroy the Wraith's tactical advantage over the other hives. The Wraith gives in and leads them out. They get to the exit but the Wraith refuses to leave without further assurances. Tyre offers to remain behind while the others get through the Stargate, and then trade the detonator for his life. The Wraith agrees and the others escape. The Wraith offers Tyre forgiveness but the Satedan says it's too late… and blows up the facility, himself, and the Wraith.
Back on Atlantis, Ronon is forced to go through withdrawal. Sheppard talks to him and Ronon says that he'll let them live if he's allowed to escape. Sheppard doesn't accept and explains that Tyre died redeeming his honor. Ronon goes through several days of intense agony as his friends watch over him. Finally he recovers and the team briefs Woolsey. He goes to his quarters for a quiet night but Teyla visits to tell him that she's formally going back on duty. She goes back to her husband and child, Rodney enjoys a bath, Woolsey enjoys classical music, and Sheppard visits Ronon and gives him Tyre's sword.