Part 1 of two. In the series premiere, Dr. Weir (Torri Higginson) lobbies Brig. Gen. O'Neill (Richard Dean Anderson) to allow her team to seek the underwater city on a faraway planet despite O'Neill's misgivings about their chances of returning to Earth. Maj. Sheppard: Joe Flanigan. Col. Sumner: Robert Patrick. Teyla: Rachel Luttrell. Daniel Jackson: Michael Shanks.

Conclusion. Cut off from Earth and menaced by the mysterious Wraith, Weir and Sheppard turn to McKay to harness the technology of Atlantis to safeguard the city and protect their team's new allies, the Athosians. Dr. McKay: David Hewlett. Lt. Ford: Rainbow Sun Francks.

McKay is trapped in a force field after altering his genes to access the Ancients' technology, and the city is rocked by systems malfunctions after a child unwittingly releases an eerie black cloud.

While fleeing from a Wraith ambush, the crew is endangered when the puddle jumper becomes lodged in the Stargate with only 38 minutes of life support available. Also, Maj. Sheppard is paralyzed by an alien symbiote.

When the Atlantis team is bushwacked by the Wraith, Dr. Weir suspects a spy is lurking among the Athosians, who resent being relocated on the basis of mere accusation.

Members of the team must make an emergency landing on a planet populated entirely by young people who willingly die in a mystic rite to protect their civilization from the Wraith. Keras: Courtenay J. Stevens.

The team discovers another planet preyed on by the Wraith---only here, the locals have been developing a drug to protect themselves from their tormentors.

The team establishes contact with the Genii, an agricultural collective whose eagerness to establish relations with Atlantis belies its true agenda. Cowen: Colm Meaney.

The team uncovers a way to travel to Earth, but after reporting the progress to Gen. Hammond, the team learns it may not be able to return to Atlantis. Simon: Garwin Sanford. Maj. Gen. Hammond: Don S. Davis.