On a distant outpost at the edge of the final frontier, an untested crew embarks on an unprecedented journey of discovery. While Commander Sisko is being interrogated by aliens inside the wormhole after being sent there by Kai Opaka, the Bajoran spiritual leader, Major Kira must deal with the Cardassian fleet who is convinced that Deep Space 9 is responsible for the disappearance of one of their ships.

Avery Brooks (Cmdr. Benjamin Sisko)
Rene Auberjonois (Odo)
Siddig El Fadil (Dr. Julian Bashir)
Terry Farrell (Lt. Jadzia Dax)
Cirroc Lofton (Jake Sisko)
Colm Meaney (Chief Miles O'Brien)
Armin Shimerman (Quark)
Nana Visitor (Major Kira Nerys)

Patrick Stewart (Captain Jean-Luc Picard)

Camille Saviola (Kai Opaka)
Felicia M. Bell (Jennifer Sisko)
Marc Alaimo (Gul Dukat)

Joel Swetow (Gul Jasad)
Aron Eisenberg (Nog)
Stephen Davies (Saratoga Tactical Officer)
Max Grodénchik (Ferengi Pit Boss [Rom])
Steve Rankin (Cardassian Officer)
Lily Mariye (Saratoga Ops Officer)
Cassandra Byram (Saratoga Conn Officer)
John Noah Hertzler (Saratoga Vulcan Captain)
April Grace (Transporter Chief Hubbell)
Kevin McDermott (Alien Batter)
Parker Whitman (Cardassian Officer)
William Powell-Blair (Cardassian Officer)
Frank Owen Smith (Curzon Dax)
Lynnda Ferguson (Doran)
Megan Butler (Enterprise Lieutenant)
Stephen Rowe (Chanting Monk)
Thomas Hobson (Young Jake Sisko)
Donald Hotton (Monk #1)
Gene Armor (Bajoran Bureaucrat)
Diana Cignoni (Dabo Girl)
Judi Durand (Cardassian Computer Voice)
Majel Barrett (Starfleet Computer Voice)

• Two-hour series pilot (production number 721). Separated into Part I and Part II for rerun (production numbers 401 and 402).
  
• Deep Space 9 originally orbited the planet Bajor. After the wormhole was discovered by Dax and Sisko in the Denorios Belt, Kira ordered the station moved to the entrance of the wormhole. The wormhole connects the Alpha to the Idran system in the Gamma Quadrant, 70,000 light years apart. The Denorios Belt is a charged plasma field located in the Bajor system, orbiting the Bajoran primary star.
  
• The episode opens with the the Battle of Wolf 359 (see also The Next Generation episode "The Best of Both Worlds, Part II"). During the battle, Lt. Cmdr. Sisko served as First Officer on the U.S.S. Saratoga (NCC-31911, Miranda-class). Sisko escaped with his son Jake, but his wife Jennifer perished during the attack.
  
• The U.S.S. Enterprise NCC-1701-D drops off Starfleet personnel, including Chief O'Brien, and three runabouts.
  
• During the opening credits for this episode, the wormhole does not appear at the end (since it hadn't been discovered yet!).
  
• Max Grodénchik is credited as "Ferengi Pit Boss." He'll later be identified as Quark's brother Rom.
  
• John Noah Hertzler (Saratoga Vulcan Captain) will change his stage name to J.G. Hertzler, and play Klingon General Martok.
  
• Production for the series began on 8/11/1992. Filming began on 8/18/1992 through 9/25/1992.