Chief O'Brien was a last-minute addition to the teleplay. Originally, the story featured a young engineering genius named Rina, whose beauty caused male colleagues to repeatedly experience pratfalls, which led to a romantic subplot with La Forge. Showrunner Maurice Hurley found the character obnoxious and deleted her when he rewrote the teleplay, replacing her with Colm Meaney's until-then nameless character, who was finally named and his personality expanded upon.
Despite having been on the ship since the series began, this is the first time that Chief O'Brien's name is used.
It took more than 20 takes for Jonathan Frakes to correctly order Worf to "initiate the quarantine transmitters on the Lantree and activate her marker beacons." After several failures, he alternated between swearing and laughing each time he botched the line.