Captain Janeway reminisces about her ancestor Shannon O'Donnel, the first of her family's long line of explorers and one who helped build the Millennium Gate on Earth. As Janeway relates the story, the episode revisits the town of Portage Creek, Indiana on New Year's Eve 2000, as Shannon O'Donnel nears the deadline to convince the town's last holdout, local bookstore owner Henry Janeway, to approve the building of massive, half a mile high Milliennium Gate, a model for the first colony on Mars.

Kate Mulgrew (Shannon O'Donnel)
Kevin Tighe (Henry Janeway)
Bradley Pierce (Jason Janeway)
John Carroll Lynch (Mr. Moss)
Christopher Curry (Driver)
James Greene (Passerby)
Kristina Hayes (Field Reporter)

• Shannon O'Donnel was an engineer who trained to be an astronaut, but was cut from the NASA space program.
  
• The Millennium Gate was a self-contained biosphere that was large enough to be seen from orbit.
  
• This episode correctly notes that the new millennium begins in the year 2001. It also predicted that the "Y2K Bug" would be a non-event.