Episode Title: "UNEXPECTED"
Production Number: 005
Original Air Date: 10-17-01
The Enterprise suffers several system malfunctions, and the crew discovers that a cloaked alien ship is closely following in their plasma wake. The Xyrillian ship's engine was malfunctioning and the Xyrillians were sharing the Enterprise's warp field.
Commander Tucker is sent over to help repair the Xyrillians' engine, but he must undergo an extended decompression process to adapt to the alien environment aboard the ship. Ah'len, a female Xyrillian engineer, befriends Tucker and gives him a demonstration of their holographic simulator that uses resequenced photons to create realistic environments.
After Tucker returns to the Enterprise, Dr. Phlox learns that Tucker's casual contact with Ah'len has resulted in his becoming pregnant, and they must find the Xyrillians again to remove the embryo. By the time the Enterprise crew locates them, the Xyrillians' engines have broken down again and they are travelling in a Klingon battle cruiser's plasma wake. Captain Archer convinces the Klingons not to destroy the Xyrillians if the aliens will share their holographic technology with the Klingons.
Factoid: The Xyrillian ship has grass growing on the floor, and the crew's food grows on the walls of the ship.
Factoid: Less than one month ago, the Enterprise returned Klaang to Qo'noS on its first mission.
Guest Characters: Porthos, *Captain Vorok
Alien Races: *Xyrillians, Klingons
KEY: [brackets]=illusions *star=first appearance