Captain Archer wants to convert curiosity into deeds and decides to enter a ship floating in space. Hoshi has trouble adjusting to life on Enterprise.

Archer sends an away team to a habitable, luscious planet for observation. But when a storm occurs, the team begins to experience paranoid delusions.

When Trip is dispatched to assist a Xyrillian ship with its power source problems, he is delighted to have a friendly encounter with one of the ship's female engineers. However, shortly after returning to Enterprise, he discovers that their seemingly innocuous interaction has led to a surprising result.

The Enterprise crew alters course to investigate the mystery of Terra Nova, a legendary Earth colony whose inhabitants mysteriously disappeared decades ago. But when they arrive, they confront descendents of the colonists who have become more alien than Archer could ever have imagined.

Enterprise visits an ancient Vulcan spiritual sanctuary, despite T'Pol's concerns that her human colleagues will be an awkward and disruptive presence there. Upon landing, they discover that the monastery has been forcibly taken over by the Andorians, a paranoid and highly excitable race of aliens with a long history of conflict with the Vulcans.

A Vulcan starship interferes with Archer's probe of an oversized comet.

Captain Archer and the crew discover a fully inhabited, civilized though less advanced Earth-like planet. Disguised to look like its inhabitants, they pay the planet an exploratory visit where they learn that a pernicious illness is afflicting the local population. As Archer seeks to help them find the malady's source, he finds himself in a close encounter with a comely female alien.

The Enterprise crew is dispatched by Starfleet Command to assist Fortunate, a human freight vessel that has been attacked by Nausicaan pirates. On arriving, they are surprised to find that Fortunate's crew is resistant to Archer's efforts to help them and determined to seek revenge against their attackers, no matter the repercussions.

When the Enterprise comes in contact with an alien vessel transporting stargazers to observe a spectacular stellar event, Archer invites them aboard the ship not realizing that Silik, a Suliban enemy, is among them. Archer quickly realizes that Silik is engaged in a nefarious time-travelling mission and must stop him before he can tamper with the course of history.