Quarantine


 * Series: Stargate Atlantis
 * Episode: 413
 * Original air date: January 18, 2008

"Quarantine" is the title of the thirteenth episode of the fourth season of Stargate Atlantis.

Plot
The crew of Atlantis is going about their normal duties when the city suddenly enacts its lockdown procedure, stranding crew members in different areas of the city. Sheppard is trapped with Teyla in McKay's lab, McKay is trapped with Katie in the greenhouse, Ronon is trapped with Keller in the infirmary, and Carter is trapped with Zelenka in an elevator. Each pair is unable to communicate with the other groups, but they all independently conclude that the city automatically locked down because it detected a dangerous contagion. The communication systems were probably shut down due to changes McKay made to the programming. Meanwhile, the lockdown program has shut down every single system in the city, ranging from communications to plumbing. It is also suspected that there may be no contagion at all, but that the city's computer suffered a malfunction. Zelenka confirms this suspicion, noting that a huge power spike caused by a weather anomaly accidentally triggered the lockdown.

While the city is locked down, each individual group attempts to cope with the situation. Because there are no computers in the greenhouse, McKay is unable to access the city's network and tries to deal with his distress with Katie, and reveals that he was intending to propose to her for marriage. However, their differing personalities begin to conflict. After a failed attempt to escape the room using an air tank, Ronon and Keller decide to wait it out, and begin to reveal personal details to each other while they await rescue. Carter and Zelenka attempt to override the transporter door, but only succeed in frying their tablet. Finally, since Sheppard and Teyla are in McKay's lab, they are the only ones able to access the city network. Fortunately, Sheppard remembers McKay's password (a combination of Newton, Einstein, McKay's date of birth, and the number 42, the answer to the the ultimate question) and uses it to log into the network. To his horror, he discovers that the city has also begun automatically broadcasting a distress signal, which could potentially compromise Atlantis' location. The only way to turn off the signal is from the control room, so Sheppard smashes the window and begins to scale the central tower from the outside to reach it. He manages to reach the control room and deactivate the signal, but that results in the city computer automatically shutting down all of the computers and initiating the self destruct sequence.

The only way to deactivate the self destruct is to shut down the city's power. In order to reach the power room, Sheppard has to go down six levels through multiple locked doors and only has a single block of C4. While moving through the city, he comes across the transporter Carter and Zelenka are trapped in and manages to free them. In order to reach the power room, they have to use the city vents. Zelenka volunteers to squeeze his way through to the power room. In the infirmary, Keller and Ronon move closer to each other and almost kiss, until Zelenka prevents the self destruct sequence and the lockdown by shutting off and turning back on the power which resets the city's systems which switches the lights off and then back on shortly after. This distracts Keller and Ronon from their very near kiss.

After everything has been resolved, everybody congratulates Zelenka for saving the city. Also, Sheppard and Teyla tease Ronon about a possible relationship between him and Keller. Meanwhile, McKay returns to Katie and admits that after the lockdown experience, he has realized that he isn't ready for marriage and doesn't want to risk ruining her life until he's worked out his own personal problems. Katie also admits that she's not quite ready for marriage either, and both she and McKay agree to put off the proposal for a future date. As Rodney heads to the door, Katie said "bye" with a very sad look on her fac

Production

 * Story By: Carl Binder
 * Teleplay By: Carl Binder


 * Directed by: Andy Mikita

Guest stars

 * Brenda James as Katie Brown