The Romulan and Klingon transporter effects of the 24th century are seen for the first time in this episode.
First Star Trek appearance of John Fleck, best known as recurring villain Silik of Suliban in Star Trek: Enterprise (2001). He also played Cardassian Overseer in The Homecoming (1993), Ornithar in The Search, Part I (1994), Koval in Inter Arma Enim Silent Leges (1999), and Abaddon in Alice (1999).
Krios in this episode looks different from Krios as seen in The Perfect Mate (1992). Here, Krios is blue; in the latter episode it is green. A reference to Krios Prime was included in "Precious Cargo" for the purpose of suggesting that the blue and green "Krios"es were two different planets.