The station goes into lockdown and the crew is endangered when an old Cardassian security program is accidentally activated.



(based upon "Star Trek" created by), (created by) | 2 more credits »

Watch Now

$0.00 with Prime Video





Episode cast overview:
Dr. Julian Bashir (as Siddig El Fadil)


O'Brien and Jake are preparing one of the old ore processing units to convert it for use as a deuterium refinery. Sisko checks up on them, just as Jake finds a strange file in the database which can't be deleted. O'Brien accidentally trips a Cardassian security alert, and must enter a password, but fails. Suddenly, the room's locked down, and a recorded message from Gul Dukat appears on view screens, warning the 'Bajoran workers' to surrender, or face consequences. But their troubles, and that of the station's, are far from over. Written by Arnoud Tiele (

Plot Summary | Add Synopsis

Plot Keywords:

24th century | See All (1) »





Release Date:

7 November 1994 (USA)  »

Company Credits

Production Co:

Show detailed on  »

Technical Specs


Sound Mix:


Aspect Ratio:

1.33 : 1
See  »

Did You Know?


"Civil Defense" resembles the Voyager episode "Worst Case Scenario". In both episodes the crew trigger a computer program which they are unable to shut down and which proves life-threatening. In "Civil Defense", the program becoming a threat to the crew was accidental. In "Worst Case Scenario", however, the program had been placed there specifically for that purpose. Coincidentally, in both episodes the programs' creators are Cardassian. See more »


Doctor Bashir: You know, I've been here nearly three years, and I was just finally starting to think of this place as home.
Major Kira: Your "home" was built by Cardassians, Doctor. Don't ever forget that.
Doctor Bashir: Well, there's not much chance of that, is there.
See more »


Star Trek: Deep Space Nine - Main Title
Written by Dennis McCarthy
Performed by Dennis McCarthy
See more »

Frequently Asked Questions

This FAQ is empty. Add the first question.

User Reviews

you might want to pass on this one
27 April 2012 | by (United States) – See all my reviews

As I write, this has a 7.8 IMDb scoring, but it's not a very good episode IMHO. Station goes into lock-down, based on an old Cardassian program in case of a Bajoran worker revolt. Which is a pretty cool idea. Then, for dramatic tension, the self-destruct countdown starts. Sound familiar? And later on, air shafts (aka, utility shafts) come into use. Aah, air shafts, the writer's best friend. There is a very clever complication about halfway through, which I enjoyed, and you might watch it for that. But otherwise this one runs just by the numbers. Just imagine what it would be like and save yourself forty minutes. If you love the show, it will be all right, but I'd recommend skipping to a better episode.

5 of 21 people found this review helpful.  Was this review helpful to you?

Message Boards

Recent Posts
OMG what was I missing! chumface
Does Quark ever get punished for his crimes? Ohio9
No security cameras on DS9? Ohio9
Fanfiction rhapsodos-31629
Catch 22 reference on Paradise Lost part 2!!!! chumface
Odo, worst ST series character... doktorx-43136
Discuss Civil Defense (1994) on the IMDb message boards »

Contribute to This Page