(written from a Production point of view)
Lorca plans to move forward with a coup against the Emperor, propelling Burnham to make a quick decision to save not only herself, but the USS Discovery.
- Please obey copyright policy; do not copy material from other sources without permission.
Act One Edit
Act Two Edit
Act Three Edit
Act Four Edit
Memorable quotes Edit
"What the hell are they doing? Is the containment field up?!"
Log entries Edit
- "Captain's log, stardate 1834.2. Acting Captain Saru recording. We are en route to the Terran flagship, having been summoned by Specialist Burnham. Discovery's spore drive is operational again, thanks to the full recovery of our navigator, Lieutenant Stamets. Yet, despite his best efforts, the lieutenant was unable to save Discovery's mycelium crop. His fear is that his Terran counterpart has already contaminated the network, and if so, the results could be catastrophic."
Background information Edit
- "What's past is prologue" is a phrase from Act 2, Scene I of William Shakespeare's The Tempest. It also inspired the title of the Star Trek: Deep Space Nine episode "Past Prologue" as well as Jake Sisko's story "Past Prologue" in DS9: "The Ascent" and the Pocket TOS novel Past Prologue.
- Shazad Latif (Ash Tyler) does not appear in this episode.
- Counting Ash Tyler as a Klingon character, this is the first Discovery episode that does not feature any Klingon.
- It's revealed the mirror Gabriel Lorca arrived in the prime universe via a transporter accident the same way Kirk, McCoy, Scott, and Uhura entered the mirror universe in 2267; in Lorca's case, it was while beaming up to ISS Buran during an ion storm.
- This is third episode of the series without a teaser after "Magic to Make the Sanest Man Go Mad" and "Si Vis Pacem, Para Bellum".
- This episode marks the first time a commanding officer has been written out of their series of origin.
Production history Edit
- 13 December 2017: Title publicly revealed 
- 28 January 2018: Premiere airdate on CBS All Access
- 29 January 2018: International release date (outside Canada and the USA)
Links and references Edit
- Sonequa Martin-Green as Michael Burnham
- Doug Jones as Saru
- Shazad Latif as Ash Tyler
- Anthony Rapp as Paul Stamets / Paul Stamets (mirror)
- Mary Wiseman as Sylvia Tilly
Special guest star Edit
Guest starring Edit
- Emily Coutts as Keyla Detmer
- Jeremy Crittenden as Lord Eling
- Patrick Kwok-Choon as Rhys
- Sara Mitich as Airiam
- Oyin Oladejo as Joann Owosekun / Joann Owosekun (mirror)
- Ronnie Rowe Jr. as Bryce
Uncredited co-stars Edit
- Bart Badzioch as ISS Charon officer
- Mustafa Bulut as ISS Charon officer
- Wilson Cruz as Hugh Culber (archive footage)
- Phi Huynh as ISS Charon officer
- Jonathan McGuire as ISS Charon officer
- Joseph Racki as ISS Charon officer
- Julie St-Louis as ISS Charon officer
Stunt doubles Edit
- Christine Ebadi as stunt double for Rekha Sharma
- Nilo Ghajar as stunt double for Sonequa Martin-Green
- Geoff Meech as stunt double for Jason Isaacs
- Melanie Phan as stunt double for Michelle Yeoh
bioweapon; black alert; Buran, ISS; Charon, ISS; clearing; containment field; emergency transport; emperor; flash grenade; forest; Harlak; hypergravity; ion storm; magnetic field; mirror universe; multiverse; mycelial energy; mycelial network; mycelial shockwave; mycelial spore; nanometer; pathway; Priors World; Starbase 46; subatomic analysis; super-mycelial reactor; superstructure; sword; terahertz
- "What's Past Is Prologue" at StarTrek.com, the official Star Trek website
- What's Past Is Prologue at Memory Beta, the wiki for licensed Star Trek works
- "Discovering the Prologue" at MissionLogPodcast.com, a Roddenberry Star Trek podcast
|Mirror universe-related episodes|
|ENT: "In a Mirror, Darkly" • "In a Mirror, Darkly, Part II"|
|DIS: "Into the Forest I Go" • "Despite Yourself" • "The Wolf Inside" • "Vaulting Ambition" • "What's Past Is Prologue"||TOS: "Mirror, Mirror"|
|DS9: "Crossover" • "Through the Looking Glass" • "Shattered Mirror" • "Resurrection" • "The Emperor's New Cloak"|
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| Star Trek: Discovery|
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"The War Without, The War Within"