The Siege, Part 1

The Siege, Part 1 is the nineteenth and penultimate episode on the first season of Stargate Atlantis.

Plot
While the Wraith come closer to Atlantis, the leading group of the expedition is informed by Dr. McKay and Dr. Zelenka that the Wraith will pass the last Ancient defense satellite; they are very confident can bring it back online and obliterate all three Hive Ships before they even reach Atlantis. McKay volunteers for the mission, and while he packs up he talks with Dr. Zelenka, who tells McKay that he should go and they even start to quarrel about it. Meanwhile Elizabeth Weir, John Sheppard and Bates search for a new Alpha site; afterwards Bates tells Sheppard that he doesn't trust Teyla but Sheppard defends his team member.

Weir is informed by Dr. Zelenka about the self-destruct of the city (mentioned in Hide and Seek as overloading the naqahdah generators) and that it wouldn't destroy enough of the city. He shows Weir a simulation which predicts that the Wraith will be able to recover some of the City's technology, and some of the database. Weir realises they have to find a way to delete the Ancients database so that the Wraith cannot recover it. Suddenly the Stargate is activated and Sheppard's team comes back. Bates assumes they were attacked by the Wraith and immediately accuses Teyla, but Sheppard then says they were attacked by some kind of T-Rex. Later Teyla confronts Bates and they start to fight until Sheppard and Lt. Ford intervene.

Meanwhile in space, the Puddle Jumper approaches the satellite and McKay enters it, wearing a spacesuit, to reactivate it. He is successful in using a Naquadah generator to power up the maintenance systems, creating an atmosphere that allows Dr. Peter Grodin and the Jumper's pilot to enter and assist with repairing the weapon, although Grodin inadvertently activates the gravity system while McKay is several feet in the air. After frustrated diagnostics, they discover that power connectors linking the weapon's energy storage buffer to the main firing system have been damaged, but to solve it someone must go outside the satellite. After drawing the short straw and much protest, McKay goes EVA. He discovers that meteor strikes have severed the connections, determines that he can reroute the power and finally is able to repair it. However, McKay has inadvertently rerouted power away from the Jumper dock, meaning they cannot dock with the satellite nor take Grodin back on board. Grodin realises there is no time to repair the fault, and he decides to stay on the satellite. This proves useful, as he will be able to keep the power levels as low as possible, ensuring the Wraith cannot detect the active system before it is ready to fire, and also to repair it if there is a problem.

At Atlantis Halling visits Weir and tells her that he doesn't want Atlantis to be destroyed. However, she tells him that she has to protect Earth. Later Weir is informed by Zelenka that he invented a virus to delete the database and Weir wants him to make a backup of it in the hard-drive they brought from Earth but he tells her that they only can save about 8%. Meanwhile Sheppard and Ford search for more potential Alpha sites until they are called because Bates was attacked and badly wounded. They ask Teyla about it but she tells them that it wasn't her.

They discuss with Weir who it could be but then Dr. Beckett finds out that there is a Wraith in the city. With a biometric sensor they are able to find out where the Wraith is and they try to capture him. However, the Wraith is able to take out Sheppard's team until he is stunned by Ford. The Wraith is imprisoned and Sheppard starts to interrogate him after he named him Bob but he keeps silent. Teyla decides to start communicate telepathically with him but he overwhelms her. Sheppard fires with his gun at him several times, wounding him badly.

Meanwhile the Wraith Hive-Ships drop out of hyperspace as predicted, and Grodin powers up the satellite. McKay watches from the cloaked Jumper as the energy beam from the weapon successfully slices through and destroys one Hive-ship. Amid the celebration, Grodin radioes that he is having trouble - McKay's rerouting has overloaded and the weapon can't be fired again. Grodin cannot bring it back online, and as McKay orders the pilot to rescue him, the remaining Hive Ships destroy the satellite, killing Grodin. McKay can't do anything, thus he informs Weir and is ordered to return to Atlantis. Weir informs the base about what has happened and afterwards starts the self-destruct countdown. Having heard the evacuation order, Bob tells them no matter where they go, no matter where they hide, the Wraith will find them, as well as Earth. A frustrated Sheppard finally kills him.